Move initializeEnvironment out of util.ts

Remove unused type parameters from Env classes
Remove InstanceURL from util.ts
2026-10-17 16:21:24 +00:00 · 2026-10-16 22:15:06 +01:00 · 2026-10-16 22:04:24 +01:00 · 2026-10-16 22:04:05 +01:00 · 2026-10-16 21:54:02 +01:00 · 2026-10-16 21:52:19 +01:00
35 changed files with 628 additions and 733 deletions
--- a/.github/copilot-instructions.md
+++ b/.github/copilot-instructions.md
@@ -11,9 +11,12 @@ The CodeQL Action is used in GitHub Actions workflows to run CodeQL scans using

 ## Review instructions

- When wording review comments, be helpful and friendly. Assume that the PR author has written the code with the best of intentions. Word your comments constructively as suggestions for improvements. Do not word suggestions as commands.
+- Prioritise identifying critical issues, such as logic bugs, over comments on documentation or typos.
+- When wording review comments, be helpful and friendly. Assume that the PR author has written the code with the best of intentions. Never word suggestions as commands or using the imperative. Examples of what you should never write: "Preserve that non-fatal behaviour here" or "Please preserve that non-fatal behaviour here".
+- When writing feedback, assume that the PR author is competent and is able to understand whether the point you are making is valid or not, why you are raising it, and how to best address it. While you can suggest how to address a point you are making, don't phrase it as a requirement or assume that it is the only solution.
+- Always word your comments constructively as suggestions for improvements, for example: "It would make sense to ..." or "Could you add ...?" or "Would it make sense to ...?"
 - If you want to comment on a change that you believe will fail a CI check, do not present the CI failure you expect as a fact. Instead, write that you think a change "may" lead to a failure in CI. Suggest that, if such a failure manifests, the changes you are commenting on may be the place responsible for the failure and are worth looking at.
- If a suggestion you make is suitable for a follow-up, such as a refactoring that doesn't change the behaviour or fixing a typo in a comment, mention that it can be addressed in a later PR rather than blocking this one.
+- If a suggestion you make is suitable for a follow-up, such as a refactoring that doesn't change the behaviour or fixing a typo in a comment, mention that it can be addressed in a later PR rather than blocking this one or prefix your comment with "Minor: ".
 - If a change is a net improvement, for example because it improves on an existing limitation of existing code, do not complain about pre-existing problems that remain. You may comment on them, but you should make it clear that the thing you are commenting on is not new by writing e.g. "Not new in this PR, but [..]" followed by your description of the issue and a suggestion that it could be improved at the same time with e.g. "Consider whether this is worth addressing as part of this PR as well."

 ## Generated code
@@ -22,6 +25,16 @@ The main codebase of the CodeQL Action is written in TypeScript and compiled to

 GitHub Actions workflows in the `.github/workflows` directory whose filenames start with two underscores (e.g. `__all-platform-bundle.yml`) are automatically generated using the `pr-checks/sync.sh` script from template files in the `pr-checks/checks` directory. Therefore, you do not need to review files in the `.github/workflows` directory that start with two underscores. However, you should review changes to the `pr-checks` directory as well as workflows in the `.github/workflows` directory that do not start with underscores.

+## Feature flags
+
+Some functionality in the code may be gated behind feature flags, which are controlled server-side. If the functionality that is gated behind them is user-facing, then this should be documented in a change note at the time that the gated functionality is added. See `CHANGELOG.md` for existing notes that mention "experimental" for examples. These typically include information about when users may expect to see the feature rolled out.
+
+When a feature flag that gates some functionality is removed, this does not need to be documented in a change note since the feature is already rolled out and the notes for the release which introduced the feature already describe it. The only exception is functionality which will start having an effect on GHES as a result of the feature flag removal:
+
+- Most functionality gated behind feature flags does not affect GHES.
+- We can make functionality available on GHES by setting `defaultValue` to `true` first and waiting for this to have had an effect on GHES. No change note is needed if a feature flag is removed where `defaultValue` was `true`.
+- When removing a feature flag where `defaultValue` was `false` and the functionality starts to affect GHES, a change note may be appropriate.
+
 ## Release process

 Changes that are merged to the `main` branch are not used in production straight away. Instead, changes from `main` must first be released using the release process, which has to be manually triggered by a staff member. Therefore, it is possible for further changes to be made to the code after some changes have been merged to `main` but before they are released. Once the release process automation is started, a series of PRs are automatically generated:
--- a/.github/workflows/__multi-language-autodetect.yml
+++ b/.github/workflows/__multi-language-autodetect.yml
@@ -192,6 +192,5 @@ jobs:
            exit 1
          fi
    env:
-      CODEQL_ACTION_CLEANUP_TOOLCACHE_BUNDLES: true
      CODEQL_ACTION_RESOLVE_SUPPORTED_LANGUAGES_USING_CLI: true
      CODEQL_ACTION_TEST_MODE: true
--- a/lib/entry-points.js
+++ b/lib/entry-points.js
@@ -34719,7 +34719,7 @@ var require_cacheUtils = __commonJS({
    var crypto3 = __importStar2(require("crypto"));
    var fs32 = __importStar2(require("fs"));
    var path30 = __importStar2(require("path"));
-    var semver11 = __importStar2(require_semver3());
+    var semver12 = __importStar2(require_semver3());
    var util4 = __importStar2(require("util"));
    var constants_1 = require_constants7();
    var versionSalt = "1.0";
@@ -34812,7 +34812,7 @@ var require_cacheUtils = __commonJS({
    function getCompressionMethod() {
      return __awaiter2(this, void 0, void 0, function* () {
        const versionOutput = yield getVersion("zstd", ["--quiet"]);
-        const version = semver11.clean(versionOutput);
+        const version = semver12.clean(versionOutput);
        core29.debug(`zstd version: ${version}`);
        if (versionOutput === "") {
          return constants_1.CompressionMethod.Gzip;
@@ -42967,11 +42967,11 @@ var require_tracingPolicy = __commonJS({
    var import_log = require_log3();
    var import_core_util = require_commonjs4();
    var import_restError = require_restError3();
-    var import_util59 = require_internal3();
+    var import_util58 = require_internal3();
    var tracingPolicyName2 = "tracingPolicy";
    function tracingPolicy2(options = {}) {
      const userAgentPromise = (0, import_userAgent.getUserAgentValue)(options.userAgentPrefix);
-      const sanitizer = new import_util59.Sanitizer({
+      const sanitizer = new import_util58.Sanitizer({
        additionalAllowedQueryParameters: options.additionalAllowedQueryParameters
      });
      const tracingClient = tryCreateTracingClient();
@@ -46597,11 +46597,11 @@ var require_response2 = __commonJS({
    });
    module2.exports = __toCommonJS2(response_exports);
    var import_core_rest_pipeline = require_commonjs6();
-    var import_util59 = require_util9();
+    var import_util58 = require_util9();
    var originalResponse = /* @__PURE__ */ Symbol("Original FullOperationResponse");
    function toCompatResponse2(response, options) {
-      let request3 = (0, import_util59.toWebResourceLike)(response.request);
-      let headers = (0, import_util59.toHttpHeadersLike)(response.headers);
+      let request3 = (0, import_util58.toWebResourceLike)(response.request);
+      let headers = (0, import_util58.toHttpHeadersLike)(response.headers);
      if (options?.createProxy) {
        return new Proxy(response, {
          get(target, prop, receiver) {
@@ -46642,7 +46642,7 @@ var require_response2 = __commonJS({
        return {
          ...compatResponse,
          headers,
-          request: (0, import_util59.toPipelineRequest)(compatResponse.request)
+          request: (0, import_util58.toPipelineRequest)(compatResponse.request)
        };
      }
    }
@@ -46749,7 +46749,7 @@ var require_requestPolicyFactoryPolicy = __commonJS({
      requestPolicyFactoryPolicyName: () => requestPolicyFactoryPolicyName2
    });
    module2.exports = __toCommonJS2(requestPolicyFactoryPolicy_exports);
-    var import_util59 = require_util9();
+    var import_util58 = require_util9();
    var import_response = require_response2();
    var HttpPipelineLogLevel2 = /* @__PURE__ */ ((HttpPipelineLogLevel22) => {
      HttpPipelineLogLevel22[HttpPipelineLogLevel22["ERROR"] = 1] = "ERROR";
@@ -46773,14 +46773,14 @@ var require_requestPolicyFactoryPolicy = __commonJS({
        async sendRequest(request3, next) {
          let httpPipeline = {
            async sendRequest(httpRequest) {
-              const response2 = await next((0, import_util59.toPipelineRequest)(httpRequest));
+              const response2 = await next((0, import_util58.toPipelineRequest)(httpRequest));
              return (0, import_response.toCompatResponse)(response2, { createProxy: true });
            }
          };
          for (const factory of orderedFactories) {
            httpPipeline = factory.create(httpPipeline, mockRequestPolicyOptions);
          }
-          const webResourceLike = (0, import_util59.toWebResourceLike)(request3, { createProxy: true });
+          const webResourceLike = (0, import_util58.toWebResourceLike)(request3, { createProxy: true });
          const response = await httpPipeline.sendRequest(webResourceLike);
          return (0, import_response.toPipelineResponse)(response);
        }
@@ -46815,12 +46815,12 @@ var require_httpClientAdapter = __commonJS({
    });
    module2.exports = __toCommonJS2(httpClientAdapter_exports);
    var import_response = require_response2();
-    var import_util59 = require_util9();
+    var import_util58 = require_util9();
    function convertHttpClient2(requestPolicyClient) {
      return {
        sendRequest: async (request3) => {
          const response = await requestPolicyClient.sendRequest(
-            (0, import_util59.toWebResourceLike)(request3, { createProxy: true })
+            (0, import_util58.toWebResourceLike)(request3, { createProxy: true })
          );
          return (0, import_response.toPipelineResponse)(response);
        }
@@ -46858,7 +46858,7 @@ var require_commonjs9 = __commonJS({
      disableKeepAlivePolicyName: () => import_disableKeepAlivePolicy.disableKeepAlivePolicyName,
      requestPolicyFactoryPolicyName: () => import_requestPolicyFactoryPolicy.requestPolicyFactoryPolicyName,
      toCompatResponse: () => import_response.toCompatResponse,
-      toHttpHeadersLike: () => import_util59.toHttpHeadersLike
+      toHttpHeadersLike: () => import_util58.toHttpHeadersLike
    });
    module2.exports = __toCommonJS2(src_exports);
    var import_extendedClient = require_extendedClient();
@@ -46866,7 +46866,7 @@ var require_commonjs9 = __commonJS({
    var import_requestPolicyFactoryPolicy = require_requestPolicyFactoryPolicy();
    var import_disableKeepAlivePolicy = require_disableKeepAlivePolicy();
    var import_httpClientAdapter = require_httpClientAdapter();
-    var import_util59 = require_util9();
+    var import_util58 = require_util9();
  }
 });

@@ -106361,7 +106361,7 @@ var require_manifest = __commonJS({
    exports2._findMatch = _findMatch;
    exports2._getOsVersion = _getOsVersion;
    exports2._readLinuxVersionFile = _readLinuxVersionFile;
-    var semver11 = __importStar2(require_semver2());
+    var semver12 = __importStar2(require_semver2());
    var core_1 = require_core();
    var os7 = require("os");
    var cp = require("child_process");
@@ -106375,7 +106375,7 @@ var require_manifest = __commonJS({
        for (const candidate of candidates) {
          const version = candidate.version;
          (0, core_1.debug)(`check ${version} satisfies ${versionSpec}`);
-          if (semver11.satisfies(version, versionSpec) && (!stable || candidate.stable === stable)) {
+          if (semver12.satisfies(version, versionSpec) && (!stable || candidate.stable === stable)) {
            file = candidate.files.find((item) => {
              (0, core_1.debug)(`${item.arch}===${archFilter} && ${item.platform}===${platFilter}`);
              let chk = item.arch === archFilter && item.platform === platFilter;
@@ -106384,7 +106384,7 @@ var require_manifest = __commonJS({
                if (osVersion === item.platform_version) {
                  chk = true;
                } else {
-                  chk = semver11.satisfies(osVersion, item.platform_version);
+                  chk = semver12.satisfies(osVersion, item.platform_version);
                }
              }
              return chk;
@@ -106644,7 +106644,7 @@ var require_tool_cache = __commonJS({
    var os7 = __importStar2(require("os"));
    var path30 = __importStar2(require("path"));
    var httpm = __importStar2(require_lib());
-    var semver11 = __importStar2(require_semver2());
+    var semver12 = __importStar2(require_semver2());
    var stream2 = __importStar2(require("stream"));
    var util4 = __importStar2(require("util"));
    var assert_1 = require("assert");
@@ -106917,7 +106917,7 @@ var require_tool_cache = __commonJS({
    }
    function cacheDir2(sourceDir, tool, version, arch2) {
      return __awaiter2(this, void 0, void 0, function* () {
-        version = semver11.clean(version) || version;
+        version = semver12.clean(version) || version;
        arch2 = arch2 || os7.arch();
        core29.debug(`Caching tool ${tool} ${version} ${arch2}`);
        core29.debug(`source dir: ${sourceDir}`);
@@ -106935,7 +106935,7 @@ var require_tool_cache = __commonJS({
    }
    function cacheFile(sourceFile, targetFile, tool, version, arch2) {
      return __awaiter2(this, void 0, void 0, function* () {
-        version = semver11.clean(version) || version;
+        version = semver12.clean(version) || version;
        arch2 = arch2 || os7.arch();
        core29.debug(`Caching tool ${tool} ${version} ${arch2}`);
        core29.debug(`source file: ${sourceFile}`);
@@ -106965,7 +106965,7 @@ var require_tool_cache = __commonJS({
      }
      let toolPath = "";
      if (versionSpec) {
-        versionSpec = semver11.clean(versionSpec) || "";
+        versionSpec = semver12.clean(versionSpec) || "";
        const cachePath = path30.join(_getCacheDirectory(), toolName, versionSpec, arch2);
        core29.debug(`checking cache: ${cachePath}`);
        if (fs32.existsSync(cachePath) && fs32.existsSync(`${cachePath}.complete`)) {
@@ -107045,7 +107045,7 @@ var require_tool_cache = __commonJS({
    }
    function _createToolPath(tool, version, arch2) {
      return __awaiter2(this, void 0, void 0, function* () {
-        const folderPath = path30.join(_getCacheDirectory(), tool, semver11.clean(version) || version, arch2 || "");
+        const folderPath = path30.join(_getCacheDirectory(), tool, semver12.clean(version) || version, arch2 || "");
        core29.debug(`destination ${folderPath}`);
        const markerPath = `${folderPath}.complete`;
        yield io9.rmRF(folderPath);
@@ -107055,15 +107055,15 @@ var require_tool_cache = __commonJS({
      });
    }
    function _completeToolPath(tool, version, arch2) {
-      const folderPath = path30.join(_getCacheDirectory(), tool, semver11.clean(version) || version, arch2 || "");
+      const folderPath = path30.join(_getCacheDirectory(), tool, semver12.clean(version) || version, arch2 || "");
      const markerPath = `${folderPath}.complete`;
      fs32.writeFileSync(markerPath, "");
      core29.debug("finished caching tool");
    }
    function isExplicitVersion(versionSpec) {
-      const c = semver11.clean(versionSpec) || "";
+      const c = semver12.clean(versionSpec) || "";
      core29.debug(`isExplicit: ${c}`);
-      const valid4 = semver11.valid(c) != null;
+      const valid4 = semver12.valid(c) != null;
      core29.debug(`explicit? ${valid4}`);
      return valid4;
    }
@@ -107071,14 +107071,14 @@ var require_tool_cache = __commonJS({
      let version = "";
      core29.debug(`evaluating ${versions.length} versions`);
      versions = versions.sort((a, b) => {
-        if (semver11.gt(a, b)) {
+        if (semver12.gt(a, b)) {
          return 1;
        }
        return -1;
      });
      for (let i = versions.length - 1; i >= 0; i--) {
        const potential = versions[i];
-        const satisfied = semver11.satisfies(potential, versionSpec);
+        const satisfied = semver12.satisfies(potential, versionSpec);
        if (satisfied) {
          version = potential;
          break;
@@ -166182,6 +166182,17 @@ var Env = class extends ReadOnlyEnv {
      core.exportVariable(name, val);
    }
  }
+  /**
+   * Set some initial environment variables that we can set even without
+   * knowing what version of CodeQL we're running.
+   */
+  initialise(version) {
+    this.export("CODEQL_ACTION_FEATURE_MULTI_LANGUAGE" /* FEATURE_MULTI_LANGUAGE */, "false");
+    this.export("CODEQL_ACTION_FEATURE_SANDWICH" /* FEATURE_SANDWICH */, "false");
+    this.export("CODEQL_ACTION_FEATURE_SARIF_COMBINE" /* FEATURE_SARIF_COMBINE */, "true");
+    this.export("CODEQL_ACTION_FEATURE_WILL_UPLOAD" /* FEATURE_WILL_UPLOAD */, "true");
+    this.export("CODEQL_ACTION_VERSION" /* VERSION */, version);
+  }
  /** Gets a value indicating whether `set` was called at least once. */
  hasChanged() {
    return this.changed;
@@ -169555,6 +169566,82 @@ function checkSchema(schema, obj, options = {}, path30 = "") {
  return result;
 }

+// src/errors/index.ts
+function wrapError(error3) {
+  return error3 instanceof Error ? error3 : new Error(String(error3));
+}
+function getErrorMessage(error3) {
+  return error3 instanceof Error ? error3.message : String(error3);
+}
+function isDiskConfigurationError(e) {
+  if (!(e instanceof Error)) {
+    return false;
+  }
+  return (
+    // out of disk space
+    e.message.includes("ENOSPC") || // access denied
+    e.message.includes("EACCES")
+  );
+}
+var ConfigurationError = class extends Error {
+};
+var HTTPError = class extends Error {
+  status;
+  constructor(message, status) {
+    super(message);
+    this.status = status;
+  }
+};
+function asHTTPError(arg) {
+  if (!isObject2(arg) || !isString(arg.message)) {
+    return void 0;
+  }
+  if (Number.isInteger(arg.status)) {
+    return new HTTPError(arg.message, arg.status);
+  }
+  if (Number.isInteger(arg.httpStatusCode)) {
+    return new HTTPError(arg.message, arg.httpStatusCode);
+  }
+  return void 0;
+}
+
+// src/github.ts
+var GITHUB_DOTCOM_URL = "https://github.com";
+function parseGitHubUrl(inputUrl) {
+  const originalUrl = inputUrl;
+  if (inputUrl.indexOf("://") === -1) {
+    inputUrl = `https://${inputUrl}`;
+  }
+  if (!inputUrl.startsWith("http://") && !inputUrl.startsWith("https://")) {
+    throw new ConfigurationError(`"${originalUrl}" is not a http or https URL`);
+  }
+  let url2;
+  try {
+    url2 = new URL(inputUrl);
+  } catch {
+    throw new ConfigurationError(`"${originalUrl}" is not a valid URL`);
+  }
+  if (url2.hostname === "github.com" || url2.hostname === "api.github.com") {
+    return GITHUB_DOTCOM_URL;
+  }
+  if (url2.pathname.indexOf("/api/v3") !== -1) {
+    url2.pathname = url2.pathname.substring(0, url2.pathname.indexOf("/api/v3"));
+  }
+  if (url2.hostname.startsWith("api.")) {
+    url2.hostname = url2.hostname.substring(4);
+  }
+  if (!url2.pathname.endsWith("/")) {
+    url2.pathname = `${url2.pathname}/`;
+  }
+  return url2.toString();
+}
+function getCurrentInstance(env) {
+  return {
+    url: env.getRequired("GITHUB_SERVER_URL" /* GITHUB_SERVER_URL */),
+    apiURL: env.getRequired("GITHUB_API_URL" /* GITHUB_API_URL */)
+  };
+}
+
 // src/util.ts
 var BASE_DATABASE_OIDS_FILE_NAME = "base-database-oids.json";
 var BROKEN_VERSIONS = ["0.0.0-20211207"];
@@ -169816,37 +169903,6 @@ var ExhaustivityCheckingError = class extends Error {
 function assertNever(value) {
  throw new ExhaustivityCheckingError(value);
 }
-function initializeEnvironment(version, env = getEnv()) {
-  env.export("CODEQL_ACTION_FEATURE_MULTI_LANGUAGE" /* FEATURE_MULTI_LANGUAGE */, "false");
-  env.export("CODEQL_ACTION_FEATURE_SANDWICH" /* FEATURE_SANDWICH */, "false");
-  env.export("CODEQL_ACTION_FEATURE_SARIF_COMBINE" /* FEATURE_SARIF_COMBINE */, "true");
-  env.export("CODEQL_ACTION_FEATURE_WILL_UPLOAD" /* FEATURE_WILL_UPLOAD */, "true");
-  env.export("CODEQL_ACTION_VERSION" /* VERSION */, version);
-}
-var HTTPError = class extends Error {
-  status;
-  constructor(message, status) {
-    super(message);
-    this.status = status;
-  }
-};
-var ConfigurationError = class extends Error {
-};
-function asHTTPError(arg) {
-  if (!isObject2(arg) || !isString(arg.message)) {
-    return void 0;
-  }
-  if (Number.isInteger(arg.status)) {
-    return new HTTPError(arg.message, arg.status);
-  }
-  if (Number.isInteger(arg.httpStatusCode)) {
-    return new HTTPError(arg.message, arg.httpStatusCode);
-  }
-  return void 0;
-}
-async function codeQlVersionAtLeast(codeql, requiredVersion) {
-  return semver.gte((await codeql.getVersion()).version, requiredVersion);
-}
 function getBaseDatabaseOidsFilePath(config) {
  return path.join(config.dbLocation, BASE_DATABASE_OIDS_FILE_NAME);
 }
@@ -169981,12 +170037,6 @@ function parseMatrixInput(matrixInput) {
    );
  }
 }
-function wrapError(error3) {
-  return error3 instanceof Error ? error3 : new Error(String(error3));
-}
-function getErrorMessage(error3) {
-  return error3 instanceof Error ? error3.message : String(error3);
-}
 function prettyPrintPack(pack) {
  return `${pack.name}${pack.version ? `@${pack.version}` : ""}${pack.path ? `:${pack.path}` : ""}`;
 }
@@ -170630,50 +170680,6 @@ retry.VERSION = VERSION7;
 // src/api-client.ts
 var import_undici = __toESM(require_undici());

-// src/github.ts
-var GITHUB_DOTCOM_URL = "https://github.com";
-var GITHUB_DOTCOM_API_URL = "https://api.github.com";
-function parseGitHubUrl(inputUrl) {
-  const originalUrl = inputUrl;
-  if (inputUrl.indexOf("://") === -1) {
-    inputUrl = `https://${inputUrl}`;
-  }
-  if (!inputUrl.startsWith("http://") && !inputUrl.startsWith("https://")) {
-    throw new ConfigurationError(`"${originalUrl}" is not a http or https URL`);
-  }
-  let url2;
-  try {
-    url2 = new URL(inputUrl);
-  } catch {
-    throw new ConfigurationError(`"${originalUrl}" is not a valid URL`);
-  }
-  if (url2.hostname === "github.com" || url2.hostname === "api.github.com") {
-    return GITHUB_DOTCOM_URL;
-  }
-  if (url2.pathname.indexOf("/api/v3") !== -1) {
-    url2.pathname = url2.pathname.substring(0, url2.pathname.indexOf("/api/v3"));
-  }
-  if (url2.hostname.startsWith("api.")) {
-    url2.hostname = url2.hostname.substring(4);
-  }
-  if (!url2.pathname.endsWith("/")) {
-    url2.pathname = `${url2.pathname}/`;
-  }
-  return url2.toString();
-}
-function getCurrentInstance(env) {
-  return {
-    url: env.getRequired("GITHUB_SERVER_URL" /* GITHUB_SERVER_URL */),
-    apiURL: env.getRequired("GITHUB_API_URL" /* GITHUB_API_URL */)
-  };
-}
-function getDotcomInstance() {
-  return {
-    url: GITHUB_DOTCOM_URL,
-    apiURL: GITHUB_DOTCOM_API_URL
-  };
-}
-
 // src/repository.ts
 function isRepositoryNwoStr(val) {
  return val.includes("/");
@@ -170738,37 +170744,6 @@ function makeProxyRequestOptions(dispatcher) {
    }
  };
 }
-var InstanceApiClient = class {
-  client;
-  apiDetails;
-  authorizationHeader;
-  constructor(apiDetails, clientOptions = {}) {
-    this.apiDetails = apiDetails;
-    this.client = createApiClientWithDetails(apiDetails, clientOptions);
-    const token = this.apiDetails.auth?.trim();
-    if (token !== void 0 && token !== "") {
-      this.authorizationHeader = `token ${token}`;
-    }
-  }
-  /**
-   * Gets a value for the `Authorization` header for a request to `url`; or `undefined` if the
-   * `Authorization` header should not be set for `url`.
-   *
-   * @param logger The logger to use for debugging messages.
-   * @param url The URL for which we want to add an `Authorization` header.
-   */
-  getAuthorizationHeaderFor(logger2, url2) {
-    if (this.authorizationHeader === void 0) {
-      return void 0;
-    }
-    if (url2.startsWith(`${this.apiDetails.url}/`) || this.apiDetails.apiURL && url2.startsWith(`${this.apiDetails.apiURL}/`)) {
-      logger2.debug(`Providing an authorization token.`);
-      return this.authorizationHeader;
-    }
-    logger2.debug(`Not using an authorization token.`);
-    return void 0;
-  }
-};
 function createApiClientWithDetails(apiDetails, { allowExternal = false, proxy = void 0 } = {}) {
  const auth2 = allowExternal && apiDetails.externalRepoAuth !== void 0 ? apiDetails.externalRepoAuth : apiDetails.auth;
  const retryingOctokit = githubUtils.GitHub.plugin(retry);
@@ -170799,19 +170774,21 @@ function getApiDetails(env = getEnv()) {
 function getApiClient(env = getEnv(), apiDetails) {
  return createApiClientWithDetails(apiDetails ?? getApiDetails(env));
 }
-function getDotcomApiDetails(env) {
-  if (env.getRequired("GITHUB_SERVER_URL" /* GITHUB_SERVER_URL */) === GITHUB_DOTCOM_URL) {
-    return getApiDetails(env);
-  } else {
-    return {
-      auth: void 0,
-      ...getDotcomInstance()
-    };
-  }
-}
 function getApiClientWithExternalAuth(apiDetails, proxy) {
  return createApiClientWithDetails(apiDetails, { allowExternal: true, proxy });
 }
+function getAuthorizationHeaderFor(logger2, apiDetails, url2) {
+  const token = apiDetails.auth?.trim();
+  if (token === void 0 || token === "") {
+    return void 0;
+  }
+  if (url2.startsWith(`${apiDetails.url}/`) || apiDetails.apiURL && url2.startsWith(`${apiDetails.apiURL}/`)) {
+    logger2.debug(`Providing an authorization token.`);
+    return `token ${token}`;
+  }
+  logger2.debug(`Not using an authorization token.`);
+  return void 0;
+}
 var cachedGitHubVersion = void 0;
 async function getGitHubVersionFromApi(apiClient, apiDetails) {
  if (parseGitHubUrl(apiDetails.url) === GITHUB_DOTCOM_URL) {
@@ -171968,11 +171945,6 @@ var featureConfig = {
    envVar: "CODEQL_ACTION_ALLOW_MULTIPLE_ANALYSIS_KINDS",
    minimumVersion: void 0
  },
-  ["cleanup_toolcache_bundles" /* CleanupToolcacheBundles */]: {
-    defaultValue: false,
-    envVar: "CODEQL_ACTION_CLEANUP_TOOLCACHE_BUNDLES",
-    minimumVersion: void 0
-  },
  ["cleanup_trap_caches" /* CleanupTrapCaches */]: {
    defaultValue: false,
    envVar: "CODEQL_ACTION_CLEANUP_TRAP_CACHES",
@@ -172291,7 +172263,7 @@ var OfflineFeatures = class {
    }
    const minimumVersion2 = config.minimumVersion;
    if (codeql && minimumVersion2) {
-      if (!await codeQlVersionAtLeast(codeql, minimumVersion2)) {
+      if (!await codeql.isVersionAtLeast(minimumVersion2)) {
        this.logger.debug(
          `Feature ${feature} is disabled because the CodeQL CLI version is older than the minimum version ${minimumVersion2}.`
        );
@@ -172714,6 +172686,7 @@ var fs16 = __toESM(require("fs"));
 var path15 = __toESM(require("path"));
 var core12 = __toESM(require_core());
 var toolrunner3 = __toESM(require_toolrunner());
+var semver10 = __toESM(require_semver2());

 // src/cli-errors.ts
 var SUPPORTED_PLATFORMS = [
@@ -174702,10 +174675,7 @@ function runnerHasSufficientDiskSpace(diskUsage, logger2, minimumDiskSpaceMb) {
  return true;
 }
 async function runnerHasSufficientMemory(codeql, ramInput, logger2) {
-  if (await codeQlVersionAtLeast(
-    codeql,
-    CODEQL_VERSION_REDUCED_OVERLAY_MEMORY_USAGE
-  )) {
+  if (await codeql.isVersionAtLeast(CODEQL_VERSION_REDUCED_OVERLAY_MEMORY_USAGE)) {
    logger2.debug(
      `Skipping memory check for overlay analysis because CodeQL version is at least ${CODEQL_VERSION_REDUCED_OVERLAY_MEMORY_USAGE}.`
    );
@@ -174843,7 +174813,7 @@ async function validateOverlayDatabaseMode(overlayDatabaseMode, useOverlayDataba
    );
    return new Failure("incompatible-build-mode" /* IncompatibleBuildMode */);
  }
-  if (!await codeQlVersionAtLeast(codeql, CODEQL_OVERLAY_MINIMUM_VERSION)) {
+  if (!await codeql.isVersionAtLeast(CODEQL_OVERLAY_MINIMUM_VERSION)) {
    logger2.warning(
      `Cannot build an ${overlayDatabaseMode} database because the CodeQL CLI is older than ${CODEQL_OVERLAY_MINIMUM_VERSION}. Falling back to creating a normal full database instead.`
    );
@@ -175817,38 +175787,38 @@ function getCodeQLActionRepository(action) {
    `The value of '${"GITHUB_ACTION_REPOSITORY" /* GITHUB_ACTION_REPOSITORY */}' is '${actionRepository}', which does not match the expected 'owner/repo' format.`
  );
 }
-var isSameDownloadSource = ([srcInstance, srcRepo], [otherInstance, otherRepo]) => {
-  return srcInstance.url === otherInstance.url && srcRepo === otherRepo;
+var DEFAULT_DOWNLOAD_SOURCE = [
+  GITHUB_DOTCOM_URL,
+  CODEQL_DEFAULT_ACTION_REPOSITORY
+];
+var isSameDownloadSource = ([srcUrl, srcRepo], [otherUrl, otherRepo]) => {
+  return srcUrl === otherUrl && srcRepo === otherRepo;
 };
 function getDefaultDotcomDownloadURL(tagName, assetName) {
  return `${GITHUB_DOTCOM_URL}/${CODEQL_DEFAULT_ACTION_REPOSITORY}/releases/download/${tagName}/${assetName}`;
 }
 async function getCodeQLAssetDownloadURL(action, apiDetails, tagName, assetName, assetKind = "CodeQL bundle") {
  const codeQLActionRepository = getCodeQLActionRepository(action);
-  const defaultDownloadSource = [
-    getDotcomApiDetails(action.env),
-    CODEQL_DEFAULT_ACTION_REPOSITORY
-  ];
  const potentialDownloadSources = [
    // This GitHub instance, and this Action.
-    [apiDetails, codeQLActionRepository],
+    [apiDetails.url, codeQLActionRepository],
    // This GitHub instance, and the canonical Action.
-    [apiDetails, CODEQL_DEFAULT_ACTION_REPOSITORY],
+    [apiDetails.url, CODEQL_DEFAULT_ACTION_REPOSITORY],
    // GitHub.com, and the canonical Action.
-    defaultDownloadSource
+    DEFAULT_DOWNLOAD_SOURCE
  ];
  const uniqueDownloadSources = potentialDownloadSources.filter(
    (source, index2, self2) => {
      return !self2.slice(0, index2).some((other) => isSameDownloadSource(source, other));
    }
  );
-  for (const [instance8, repository] of uniqueDownloadSources) {
-    if (isSameDownloadSource(defaultDownloadSource, [instance8, repository])) {
+  for (const [instanceURL, repository] of uniqueDownloadSources) {
+    if (isSameDownloadSource(DEFAULT_DOWNLOAD_SOURCE, [instanceURL, repository])) {
      break;
    }
    const { owner: repositoryOwner, repo: repositoryName } = parseRepositoryNwo(repository);
    try {
-      const release2 = await getApiClient(action.env, instance8).rest.repos.getReleaseByTag({
+      const release2 = await getApiClient().rest.repos.getReleaseByTag({
        owner: repositoryOwner,
        repo: repositoryName,
        tag: tagName
@@ -175856,14 +175826,14 @@ async function getCodeQLAssetDownloadURL(action, apiDetails, tagName, assetName,
      for (const asset of release2.data.assets) {
        if (asset.name === assetName) {
          action.logger.info(
-            `Found ${assetKind} ${assetName} in ${repository} on ${instance8.apiURL} with URL ${asset.url}.`
+            `Found ${assetKind} ${assetName} in ${repository} on ${instanceURL} with URL ${asset.url}.`
          );
          return asset.url;
        }
      }
    } catch (e) {
      action.logger.info(
-        `Looked for ${assetKind} ${assetName} in ${repository} on ${instance8.apiURL} but got error ${e}.`
+        `Looked for ${assetKind} ${assetName} in ${repository} on ${instanceURL} but got error ${e}.`
      );
    }
  }
@@ -176684,8 +176654,7 @@ async function getCodeQLSource(toolsInput, defaultCliVersion, rawLanguages, othe
    cliVersion: cliVersion2,
    compressionMethod,
    sourceType: "download",
-    toolsVersion: resolvedVersion ?? "unknown",
-    apiDetails
+    toolsVersion: resolvedVersion ?? "unknown"
  };
 }
 async function tryGetFallbackToolcacheVersion(cliVersion2, tagName, logger2) {
@@ -176699,7 +176668,7 @@ async function tryGetFallbackToolcacheVersion(cliVersion2, tagName, logger2) {
  );
  return fallbackVersion;
 }
-var downloadCodeQL = async function(source, tarVersion, tempDir, logger2) {
+var downloadCodeQL = async function(source, apiDetails, tarVersion, tempDir, logger2) {
  const { bundle, compressionMethod } = source;
  const codeqlURL = bundle.url;
  const parsedCodeQLURL = new URL(codeqlURL);
@@ -176711,8 +176680,11 @@ var downloadCodeQL = async function(source, tarVersion, tempDir, logger2) {
  if (searchParams.has("token")) {
    logger2.debug("CodeQL tools URL contains an authorization token.");
  } else {
-    const client = new InstanceApiClient(source.apiDetails);
-    authorization = client.getAuthorizationHeaderFor(logger2, codeqlURL);
+    authorization = getAuthorizationHeaderFor(
+      logger2,
+      apiDetails,
+      codeqlURL
+    );
  }
  const toolcacheDestination = getToolcacheDestination({ logger: logger2 }, source);
  const extractedBundlePath = toolcacheDestination.orElse(
@@ -176763,7 +176735,6 @@ function getToolcacheDestination({ logger: logger2 }, source) {
 }
 async function tryDeleteToolcacheBundles({
  env,
-  features,
  logger: logger2
 }) {
  if (env.getOptional("CODEQL_ACTION_HAS_SET_UP_CODEQL" /* HAS_SET_UP_CODEQL */) !== void 0) {
@@ -176772,7 +176743,7 @@ async function tryDeleteToolcacheBundles({
    );
    return;
  }
-  if (!isGitHubHostedRunner() || !isToolcacheOnWorkspaceFilesystem(logger2) || !await features.getValue("cleanup_toolcache_bundles" /* CleanupToolcacheBundles */)) {
+  if (!isGitHubHostedRunner(env) || !isToolcacheOnWorkspaceFilesystem(logger2)) {
    return;
  }
  const result = await deleteToolcacheBundles({ env, logger: logger2 });
@@ -176832,8 +176803,9 @@ async function setupCodeQLBundle(toolsInput, apiDetails, tempDir, variant, defau
      break;
    case "download": {
      const result = await downloadCodeQLBundle(
-        { env: getEnv(), features, logger: logger2 },
+        { env: getEnv(), logger: logger2 },
        source,
+        apiDetails,
        zstdAvailability.version,
        tempDir
      );
@@ -176853,13 +176825,19 @@ async function setupCodeQLBundle(toolsInput, apiDetails, tempDir, variant, defau
    toolsVersion: source.toolsVersion
  };
 }
-async function downloadCodeQLBundle(action, source, tarVersion, tempDir) {
+async function downloadCodeQLBundle(action, source, apiDetails, tarVersion, tempDir) {
  const { bundle } = source;
  const { logger: logger2 } = action;
  await tryDeleteToolcacheBundles(action);
  const startTime = import_perf_hooks4.performance.now();
  try {
-    return await downloadCodeQL(source, tarVersion, tempDir, logger2);
+    return await downloadCodeQL(
+      source,
+      apiDetails,
+      tarVersion,
+      tempDir,
+      logger2
+    );
  } catch (e) {
    if (bundle.kind !== "per-language" || bundle.combinedBundleURL === void 0 || asHTTPError(e)?.status !== 404) {
      throw e;
@@ -176870,6 +176848,7 @@ async function downloadCodeQLBundle(action, source, tarVersion, tempDir) {
        ...source,
        bundle: { kind: "combined", url: bundle.combinedBundleURL }
      },
+      apiDetails,
      tarVersion,
      tempDir,
      logger2
@@ -177034,16 +177013,6 @@ var CODEQL_NEXT_MINIMUM_VERSION = "2.21.3";
 var GHES_VERSION_MOST_RECENTLY_DEPRECATED = "3.17";
 var GHES_MOST_RECENT_DEPRECATION_DATE = "2026-09-24";
 var EXTRACTION_DEBUG_MODE_VERBOSITY = "progress++";
-function isDiskConfigurationError(e) {
-  if (!(e instanceof Error)) {
-    return false;
-  }
-  return (
-    // out of disk space
-    e.message.includes("ENOSPC") || // access denied
-    e.message.includes("EACCES")
-  );
-}
 async function setupCodeQL(toolsInput, apiDetails, tempDir, variant, defaultCliVersion, rawLanguages, otherLanguagePacksReason, useOverlayAwareDefaultCliVersion, features, logger2, checkVersion) {
  try {
    const {
@@ -177118,6 +177087,9 @@ async function getCodeQLForCmd(logger2, cmd, checkVersion) {
      }
      return result;
    },
+    async isVersionAtLeast(requiredVersion) {
+      return semver10.gte((await this.getVersion()).version, requiredVersion);
+    },
    async printVersion() {
      core12.info(JSON.stringify(await this.getVersion(), null, 2));
    },
@@ -177506,11 +177478,11 @@ Output was: ${extractorPath}`
      await runCli(cmd, args);
    }
  };
-  if (checkVersion && !await codeQlVersionAtLeast(codeql, CODEQL_MINIMUM_VERSION)) {
+  if (checkVersion && !await codeql.isVersionAtLeast(CODEQL_MINIMUM_VERSION)) {
    throw new ConfigurationError(
      `Expected a CodeQL CLI with version at least ${CODEQL_MINIMUM_VERSION} but got version ${(await codeql.getVersion()).version}`
    );
-  } else if (checkVersion && process.env["CODEQL_ACTION_SUPPRESS_DEPRECATED_SOON_WARNING" /* SUPPRESS_DEPRECATED_SOON_WARNING */] !== "true" && !await codeQlVersionAtLeast(codeql, CODEQL_NEXT_MINIMUM_VERSION)) {
+  } else if (checkVersion && process.env["CODEQL_ACTION_SUPPRESS_DEPRECATED_SOON_WARNING" /* SUPPRESS_DEPRECATED_SOON_WARNING */] !== "true" && !await codeql.isVersionAtLeast(CODEQL_NEXT_MINIMUM_VERSION)) {
    const result = await codeql.getVersion();
    core12.warning(
      `CodeQL CLI version ${result.version} was discontinued on ${GHES_MOST_RECENT_DEPRECATION_DATE} alongside GitHub Enterprise Server ${GHES_VERSION_MOST_RECENTLY_DEPRECATED} and will not be supported by the next minor release of the CodeQL Action. Please update to CodeQL CLI version ${CODEQL_NEXT_MINIMUM_VERSION} or later. For instance, if you have specified a custom version of the CLI using the 'tools' input to the 'init' Action, you can remove this input to use the default version.
@@ -178527,8 +178499,8 @@ async function recordClearCleanupSizes(codeql, config, reports, logger2) {
    report.clear_cleanup_measurement_duration_ms = durationMs;
  }
 }
-async function uploadBundledDatabase(repositoryNwo, language, commitOid, bundledDb, bundledDbSize, apiDetails, env = getEnv()) {
-  const client = getApiClient(env, apiDetails);
+async function uploadBundledDatabase(repositoryNwo, language, commitOid, bundledDb, bundledDbSize, apiDetails) {
+  const client = getApiClient(getEnv(), apiDetails);
  const uploadsUrl = new URL(parseGitHubUrl(apiDetails.url));
  uploadsUrl.hostname = `uploads.${uploadsUrl.hostname}`;
  let uploadsBaseUrl = uploadsUrl.toString();
@@ -180791,7 +180763,7 @@ async function run(action) {
  let dependencyCacheResults;
  let databaseUploadResults = [];
  try {
-    initializeEnvironment(getActionVersion());
+    action.env.initialise(getActionVersion());
    persistInputs();
    const statusReportBase = await createStatusReportBase(
      "finish" /* Analyze */,
@@ -183122,7 +183094,7 @@ var import_async = __toESM(require_async(), 1);
 var import_path7 = require("path");

 // node_modules/archiver/lib/error.js
-var import_util37 = __toESM(require("util"), 1);
+var import_util36 = __toESM(require("util"), 1);
 var ERROR_CODES = {
  ABORTED: "archive was aborted",
  DIRECTORYDIRPATHREQUIRED: "diretory dirpath argument must be a non-empty string value",
@@ -183147,7 +183119,7 @@ function ArchiverError(code, data) {
  this.code = code;
  this.data = data;
 }
-import_util37.default.inherits(ArchiverError, Error);
+import_util36.default.inherits(ArchiverError, Error);

 // node_modules/archiver/lib/core.js
 var import_readable_stream2 = __toESM(require_ours(), 1);
@@ -185970,8 +185942,8 @@ async function runWrapper2() {

 // src/autobuild-action.ts
 var core17 = __toESM(require_core());
-async function sendCompletedStatusReport(config, logger2, startedAt, allLanguages, failingLanguage, cause) {
-  initializeEnvironment(getActionVersion());
+async function sendCompletedStatusReport(env, config, logger2, startedAt, allLanguages, failingLanguage, cause) {
+  env.initialise(getActionVersion());
  const status = getActionsStatus(cause, failingLanguage);
  const statusReportBase = await createStatusReportBase(
    "autobuild" /* Autobuild */,
@@ -186043,6 +186015,7 @@ async function run2({
      `We were unable to automatically build your code. Please replace the call to the autobuild action with your custom build steps. ${error3.message}`
    );
    await sendCompletedStatusReport(
+      env,
      config,
      logger2,
      startedAt,
@@ -186053,7 +186026,13 @@ async function run2({
    return;
  }
  env.export("CODEQL_ACTION_AUTOBUILD_DID_COMPLETE_SUCCESSFULLY" /* AUTOBUILD_DID_COMPLETE_SUCCESSFULLY */, "true");
-  await sendCompletedStatusReport(config, logger2, startedAt, languages ?? []);
+  await sendCompletedStatusReport(
+    env,
+    config,
+    logger2,
+    startedAt,
+    languages ?? []
+  );
 }
 var autobuild = {
  name: "autobuild" /* Autobuild */,
@@ -186068,7 +186047,7 @@ var fs29 = __toESM(require("fs"));
 var path25 = __toESM(require("path"));
 var core19 = __toESM(require_core());
 var io7 = __toESM(require_io());
-var semver10 = __toESM(require_semver2());
+var semver11 = __toESM(require_semver2());

 // src/config/inputs.ts
 async function getToolsInput(action, repositoryProperties) {
@@ -186481,7 +186460,7 @@ async function run3(actionState) {
  let toolsSource;
  let toolsVersion;
  try {
-    initializeEnvironment(getActionVersion());
+    actionState.env.initialise(getActionVersion());
    persistInputs();
    apiDetails = {
      auth: getRequiredInput("token"),
@@ -186578,7 +186557,7 @@ async function run3(actionState) {
    ) {
      const publicPreview = "2.22.1";
      const actualVer = (await codeql.getVersion()).version;
-      if (semver10.lt(actualVer, publicPreview)) {
+      if (semver11.lt(actualVer, publicPreview)) {
        actionState.env.export("CODEQL_ENABLE_EXPERIMENTAL_FEATURES" /* EXPERIMENTAL_FEATURES */, "true");
        logger2.info("Experimental Rust analysis enabled");
      }
@@ -186811,7 +186790,7 @@ exec ${goBinaryPath} "$@"`
      logger2.debug(
        `${"CODEQL_EXTRACTOR_JAVA_OPTION_MINIMIZE_DEPENDENCY_JARS" /* JAVA_EXTRACTOR_MINIMIZE_DEPENDENCY_JARS */} is already set to '${process.env["CODEQL_EXTRACTOR_JAVA_OPTION_MINIMIZE_DEPENDENCY_JARS" /* JAVA_EXTRACTOR_MINIMIZE_DEPENDENCY_JARS */]}', so the Action will not override it.`
      );
-    } else if (await codeQlVersionAtLeast(codeql, CODEQL_VERSION_JAR_MINIMIZATION) && config.dependencyCachingEnabled && config.buildMode === "none" /* None */ && config.languages.includes("java" /* java */)) {
+    } else if (await codeql.isVersionAtLeast(CODEQL_VERSION_JAR_MINIMIZATION) && config.dependencyCachingEnabled && config.buildMode === "none" /* None */ && config.languages.includes("java" /* java */)) {
      actionState.env.export(
        "CODEQL_EXTRACTOR_JAVA_OPTION_MINIMIZE_DEPENDENCY_JARS" /* JAVA_EXTRACTOR_MINIMIZE_DEPENDENCY_JARS */,
        "true"
@@ -187524,7 +187503,7 @@ async function run6(actionState) {
  let toolsSource;
  let toolsVersion;
  try {
-    initializeEnvironment(getActionVersion());
+    actionState.env.initialise(getActionVersion());
    const apiDetails = {
      auth: getRequiredInput("token"),
      externalRepoAuth: getOptionalInput("external-repository-token"),
@@ -187946,7 +187925,6 @@ async function getProxyBinaryPath(action, apiDetails) {
  const logger2 = action.logger;
  logger2.startGroup("Setting up authentication proxy");
  try {
-    const client = new InstanceApiClient(apiDetails);
    const proxyFileName = getProxyFilename();
    const proxyInfo = await getDownloadUrl(action, apiDetails);
    logger2.info(
@@ -187957,8 +187935,9 @@ async function getProxyBinaryPath(action, apiDetails) {
      logger2.info(
        `Authentication proxy is not in the toolcache. Will try to download it from '${proxyInfo.url}'.`
      );
-      const authorization = client.getAuthorizationHeaderFor(
+      const authorization = getAuthorizationHeaderFor(
        logger2,
+        apiDetails,
        proxyInfo.url
      );
      const temp = await downloadProxy(logger2, proxyInfo.url, authorization);
@@ -188476,9 +188455,10 @@ async function sendSuccessStatusReport2(startedAt, uploadStats, logger2) {
    await sendStatusReport(statusReport);
  }
 }
-async function run8({ startedAt, logger: logger2 }) {
+async function run8(action) {
+  const logger2 = action.logger;
  try {
-    initializeEnvironment(getActionVersion());
+    action.env.initialise(getActionVersion());
    const gitHubVersion = await getGitHubVersion();
    checkActionVersion(getActionVersion(), gitHubVersion);
    persistInputs();
@@ -188492,7 +188472,7 @@ async function run8({ startedAt, logger: logger2 }) {
    const startingStatusReportBase = await createStatusReportBase(
      "upload-sarif" /* UploadSarif */,
      "starting",
-      startedAt,
+      action.startedAt,
      void 0,
      await checkDiskUsage(logger2),
      logger2
@@ -188535,7 +188515,7 @@ async function run8({ startedAt, logger: logger2 }) {
      }
    }
    await sendSuccessStatusReport2(
-      startedAt,
+      action.startedAt,
      codeScanningResult?.statusReport || {},
      logger2
    );
@@ -188546,7 +188526,7 @@ async function run8({ startedAt, logger: logger2 }) {
    const errorStatusReportBase = await createStatusReportBase(
      "upload-sarif" /* UploadSarif */,
      getActionsStatus(error3),
-      startedAt,
+      action.startedAt,
      void 0,
      await checkDiskUsage(logger2),
      logger2,
--- a/pr-checks/checks/multi-language-autodetect.yml
+++ b/pr-checks/checks/multi-language-autodetect.yml
@@ -14,7 +14,6 @@ operatingSystems:
      - stable-v2.21.4
      - stable-v2.22.4
 env:
-  CODEQL_ACTION_CLEANUP_TOOLCACHE_BUNDLES: true
  CODEQL_ACTION_RESOLVE_SUPPORTED_LANGUAGES_USING_CLI: true
 installGo: true
 installDotNet: true
--- a/src/actions-util.test.ts
+++ b/src/actions-util.test.ts
@@ -12,8 +12,8 @@ import {
 import { computeAutomationID } from "./api-client";
 import { EnvVar } from "./environment";
 import { getRunnerLogger } from "./logging";
-import { RecordingLogger, setupTests } from "./testing-utils";
-import { initializeEnvironment, withTmpDir } from "./util";
+import { getTestEnv, RecordingLogger, setupTests } from "./testing-utils";
+import { withTmpDir } from "./util";

 setupTests(test);

@@ -228,8 +228,9 @@ test.serial(
 );

 test.serial("initializeEnvironment", (t) => {
-  initializeEnvironment("1.2.3");
-  t.deepEqual(process.env[EnvVar.VERSION], "1.2.3");
+  const env = getTestEnv();
+  env.initialise("1.2.3");
+  t.deepEqual(env.getOptional(EnvVar.VERSION), "1.2.3");
 });

 test.serial("fixCodeQualityCategory", (t) => {
--- a/src/analyze-action.ts
+++ b/src/analyze-action.ts
@@ -238,7 +238,7 @@ async function run(action: ActionState<["Base", "Logger", "Env", "Actions"]>) {
  let databaseUploadResults: DatabaseUploadResult[] = [];

  try {
-    util.initializeEnvironment(actionsUtil.getActionVersion());
+    action.env.initialise(actionsUtil.getActionVersion());

    // Make inputs accessible in the `post` step, details at
    // https://github.com/github/codeql-action/issues/2553
--- a/src/api-client.test.ts
+++ b/src/api-client.test.ts
@@ -7,7 +7,7 @@ import { ProxyAgent } from "undici";
 import * as actionsUtil from "./actions-util";
 import * as api from "./api-client";
 import { DO_NOT_RETRY_STATUSES } from "./api-client";
-import { ActionsEnvVars, RegistryProxyVars } from "./environment";
+import { ActionsEnvVars, RegistryProxyVars, getEnv } from "./environment";
 import { GITHUB_DOTCOM_API_URL, GITHUB_DOTCOM_URL } from "./github";
 import {
  callee,
@@ -21,7 +21,7 @@ import * as util from "./util";
 setupTests(test);

 test.beforeEach(() => {
-  util.initializeEnvironment(actionsUtil.getActionVersion());
+  getEnv().initialise(actionsUtil.getActionVersion());
 });

 test.serial("getApiClient", async (t) => {
@@ -308,45 +308,70 @@ test.serial(
 test("getAuthorizationHeaderFor - returns undefined if there's no token", (t) => {
  const logger = new RecordingLogger();

-  for (const authValue of [undefined, "", "    "]) {
-    const client = new api.InstanceApiClient({
-      ...SAMPLE_DOTCOM_API_DETAILS,
-      auth: authValue,
-    });
-    t.is(
-      client.getAuthorizationHeaderFor(logger, `${GITHUB_DOTCOM_URL}/github`),
-      undefined,
-    );
-  }
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      { ...SAMPLE_DOTCOM_API_DETAILS, auth: undefined },
+      `${GITHUB_DOTCOM_URL}/github`,
+    ),
+    undefined,
+  );
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      { ...SAMPLE_DOTCOM_API_DETAILS, auth: "" },
+      `${GITHUB_DOTCOM_URL}/github`,
+    ),
+    undefined,
+  );
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      { ...SAMPLE_DOTCOM_API_DETAILS, auth: "    " },
+      `${GITHUB_DOTCOM_URL}/github`,
+    ),
+    undefined,
+  );
 });

 test("getAuthorizationHeaderFor - returns header value with token if url is allowed", (t) => {
  const logger = new RecordingLogger();
-  const client = new api.InstanceApiClient({
-    ...SAMPLE_DOTCOM_API_DETAILS,
-  });

-  for (const url of [
-    `${GITHUB_DOTCOM_URL}/github`,
-    `${GITHUB_DOTCOM_API_URL}/github`,
-  ]) {
-    t.is(
-      client.getAuthorizationHeaderFor(logger, url),
-      `token ${SAMPLE_DOTCOM_API_DETAILS.auth}`,
-    );
-  }
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      SAMPLE_DOTCOM_API_DETAILS,
+      `${GITHUB_DOTCOM_URL}/github`,
+    ),
+    `token ${SAMPLE_DOTCOM_API_DETAILS.auth}`,
+  );
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      SAMPLE_DOTCOM_API_DETAILS,
+      `${GITHUB_DOTCOM_API_URL}/github`,
+    ),
+    `token ${SAMPLE_DOTCOM_API_DETAILS.auth}`,
+  );
 });

 test("getAuthorizationHeaderFor - returns undefined if url is not allowed", (t) => {
  const logger = new RecordingLogger();
-  const client = new api.InstanceApiClient({
-    ...SAMPLE_DOTCOM_API_DETAILS,
-  });

-  for (const url of [
-    `https://localhost/github`,
-    `https://api.localhost/github`,
-  ]) {
-    t.is(client.getAuthorizationHeaderFor(logger, url), undefined);
-  }
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      SAMPLE_DOTCOM_API_DETAILS,
+      `https://localhost/github`,
+    ),
+    undefined,
+  );
+  t.is(
+    api.getAuthorizationHeaderFor(
+      logger,
+      SAMPLE_DOTCOM_API_DETAILS,
+      `https://api.localhost/github`,
+    ),
+    undefined,
+  );
 });
--- a/src/api-client.ts
+++ b/src/api-client.ts
@@ -18,11 +18,9 @@ import {
  RegistryProxyVars,
  getEnv,
  exportEnvVar,
-  ActionsEnvVars,
 } from "./environment";
 import {
  getCurrentInstance,
-  getDotcomInstance,
  GITHUB_DOTCOM_URL,
  parseGitHubUrl,
  type GitHubApiCombinedDetails,
@@ -122,66 +120,6 @@ export function makeProxyRequestOptions(
 /** The type of GitHub API client we use. */
 export type ApiClient = InstanceType<typeof githubUtils.GitHub>;

-/**
- * Encapsulates a {@link GitHubApiCombinedDetails} along with operations which ensure that any credentials
- * are only used with the GitHub instance that is represented by the {@link GitHubApiCombinedDetails} value.
- */
-export class InstanceApiClient {
-  private readonly client: ApiClient;
-  private readonly apiDetails: GitHubApiCombinedDetails;
-  private readonly authorizationHeader: string | undefined;
-
-  constructor(
-    apiDetails: GitHubApiCombinedDetails,
-    clientOptions: CreateApiClientOptions = {},
-  ) {
-    this.apiDetails = apiDetails;
-    this.client = createApiClientWithDetails(apiDetails, clientOptions);
-
-    // Compute the Authorization header value if we have a token.
-    const token = this.apiDetails.auth?.trim();
-    if (token !== undefined && token !== "") {
-      this.authorizationHeader = `token ${token}`;
-    }
-  }
-
-  /**
-   * In most cases, we use an {@link ApiClient} which automatically handles auth for requests
-   * made with it and this method is not needed and should not be used in that setting.
-   *
-   * In some cases, we need to make requests that can't go through an {@link ApiClient}, but still
-   * require auth. For example, this is the case when using the `toolcache` module to download
-   * files. For these cases, this method gets a value for the `Authorization` header for a request
-   * to `url`; or `undefined` if the `Authorization` header should not be set for `url`.
-   *
-   * @param logger The logger to use for debugging messages.
-   * @param url The URL for which we want to add an `Authorization` header.
-   */
-  public getAuthorizationHeaderFor(
-    logger: Logger,
-    url: string,
-  ): string | undefined {
-    // We don't have to check the `url` if we don't have a token to begin with.
-    if (this.authorizationHeader === undefined) {
-      return undefined;
-    }
-
-    // We only want to provide an authorization header if we are downloading
-    // from the same GitHub instance the Action is running on.
-    // This avoids leaking Enterprise tokens to dotcom.
-    if (
-      url.startsWith(`${this.apiDetails.url}/`) ||
-      (this.apiDetails.apiURL && url.startsWith(`${this.apiDetails.apiURL}/`))
-    ) {
-      logger.debug(`Providing an authorization token.`);
-      return this.authorizationHeader;
-    }
-
-    logger.debug(`Not using an authorization token.`);
-    return undefined;
-  }
-}
-
 /** Options for `createApiClientWithDetails`. */
 interface CreateApiClientOptions {
  allowExternal?: boolean;
@@ -234,8 +172,8 @@ export function getApiDetails(env: ReadOnlyEnv = getEnv()): GitHubApiDetails {
 /**
 * Constructs an {@link ApiClient} using {@link apiDetails}.
 *
- * If {@link apiDetails} is not specified, then the GitHub instance URLs are taken from {@link env}
- * and the auth token is taken from the `token` input.
+ * If {@link apiDetails} is not specified, then the GitHub instance URLs and auth token
+ * are taken from {@link env}.
 *
 * If {@link env} is not specified, then the process environment is used.
 *
@@ -249,28 +187,6 @@ export function getApiClient(
  return createApiClientWithDetails(apiDetails ?? getApiDetails(env));
 }

-/*
- * Gets a `GitHubApiDetails` object describing the GitHub Dotcom instance.
- *
- * @param env The environment variables to read.
- */
-export function getDotcomApiDetails(env: ReadOnlyEnv): GitHubApiDetails {
-  // If we are currently running on dotcom, then just call `getApiDetails` which will
-  // construct the appropriate `GitHubApiDetails` from the environment and include the
-  // value of the `token` input. The `token` input relates to the GitHub instance that
-  // we are running on only. Therefore, if we are not currently running on dotcom,
-  // then we construct `GitHubApiDetails` without the `token` value and using the
-  // hard-coded instance and API URLs.
-  if (env.getRequired(ActionsEnvVars.GITHUB_SERVER_URL) === GITHUB_DOTCOM_URL) {
-    return getApiDetails(env);
-  } else {
-    return {
-      auth: undefined,
-      ...getDotcomInstance(),
-    };
-  }
-}
-
 export function getApiClientWithExternalAuth(
  apiDetails: GitHubApiCombinedDetails,
  proxy?: ProxyAgent,
@@ -278,6 +194,42 @@ export function getApiClientWithExternalAuth(
  return createApiClientWithDetails(apiDetails, { allowExternal: true, proxy });
 }

+/**
+ * Gets a value for the `Authorization` header for a request to `url`; or `undefined` if the
+ * `Authorization` header should not be set for `url`.
+ *
+ * @param logger The logger to use for debugging messages.
+ * @param apiDetails Details of the GitHub API we are using.
+ * @param url The URL for which we want to add an `Authorization` header.
+ *
+ * @returns The value for the `Authorization` header or `undefined` if it shouldn't be populated.
+ */
+export function getAuthorizationHeaderFor(
+  logger: Logger,
+  apiDetails: GitHubApiDetails,
+  url: string,
+): string | undefined {
+  // We don't have to check the `url` if we don't have a token to begin with.
+  const token = apiDetails.auth?.trim();
+  if (token === undefined || token === "") {
+    return undefined;
+  }
+
+  // We only want to provide an authorization header if we are downloading
+  // from the same GitHub instance the Action is running on.
+  // This avoids leaking Enterprise tokens to dotcom.
+  if (
+    url.startsWith(`${apiDetails.url}/`) ||
+    (apiDetails.apiURL && url.startsWith(`${apiDetails.apiURL}/`))
+  ) {
+    logger.debug(`Providing an authorization token.`);
+    return `token ${token}`;
+  }
+
+  logger.debug(`Not using an authorization token.`);
+  return undefined;
+}
+
 let cachedGitHubVersion: GitHubVersion | undefined = undefined;

 export async function getGitHubVersionFromApi(
--- a/src/autobuild-action.ts
+++ b/src/autobuild-action.ts
@@ -10,7 +10,7 @@ import { getGitHubVersion } from "./api-client";
 import { determineAutobuildLanguages, runAutobuild } from "./autobuild";
 import { getCodeQL } from "./codeql";
 import { Config, getConfig } from "./config-utils";
-import { EnvVar } from "./environment";
+import { EnvVar, type Env } from "./environment";
 import { Language } from "./languages";
 import { Logger } from "./logging";
 import {
@@ -26,7 +26,6 @@ import {
  checkDiskUsage,
  checkGitHubVersionInRange,
  ConfigurationError,
-  initializeEnvironment,
  wrapError,
 } from "./util";

@@ -38,6 +37,7 @@ interface AutobuildStatusReport extends StatusReportBase {
 }

 async function sendCompletedStatusReport(
+  env: Env,
  config: Config | undefined,
  logger: Logger,
  startedAt: Date,
@@ -45,7 +45,7 @@ async function sendCompletedStatusReport(
  failingLanguage?: string,
  cause?: Error,
 ) {
-  initializeEnvironment(getActionVersion());
+  env.initialise(getActionVersion());

  const status = getActionsStatus(cause, failingLanguage);
  const statusReportBase = await createStatusReportBase(
@@ -129,6 +129,7 @@ async function run({
      `We were unable to automatically build your code. Please replace the call to the autobuild action with your custom build steps. ${error.message}`,
    );
    await sendCompletedStatusReport(
+      env,
      config,
      logger,
      startedAt,
@@ -141,7 +142,13 @@ async function run({

  env.export(EnvVar.AUTOBUILD_DID_COMPLETE_SUCCESSFULLY, "true");

-  await sendCompletedStatusReport(config, logger, startedAt, languages ?? []);
+  await sendCompletedStatusReport(
+    env,
+    config,
+    logger,
+    startedAt,
+    languages ?? [],
+  );
 }

 /** Defines the `autobuild` Action. */
--- a/src/codeql-bundle.ts
+++ b/src/codeql-bundle.ts
@@ -1,4 +1,3 @@
-import type { GitHubApiDetails } from "./github";
 import { BuiltInLanguage, parseBuiltInLanguage } from "./languages";
 import { BundlePlatform } from "./platform";
 import type { CompressionMethod } from "./tar";
@@ -18,8 +17,6 @@ export type CodeQLBundle =
 export interface CodeQLDownloadSource {
  /** Distinguishes downloads from local archives and cached installations. */
  sourceType: "download";
-  /** Information about the GitHub instance that contains the asset. */
-  apiDetails: GitHubApiDetails;
  /** The bundle to download. */
  bundle: CodeQLBundle;
  /** The compression format of the bundle archive. */
--- a/src/codeql.test.ts
+++ b/src/codeql.test.ts
@@ -21,6 +21,7 @@ import {
 import type { Config } from "./config-utils";
 import * as defaults from "./defaults.json";
 import { DocUrl } from "./doc-url";
+import { getEnv } from "./environment";
 import { BuiltInLanguage } from "./languages";
 import { getRunnerLogger } from "./logging";
 import { ToolsSource } from "./setup-codeql";
@@ -34,18 +35,16 @@ import {
  makeVersionInfo,
  createTestConfig,
  makeMacro,
-  mockApiDetails,
 } from "./testing-utils";
 import { ToolsDownloadStatusReport } from "./tools-download";
 import * as util from "./util";
-import { initializeEnvironment } from "./util";

 setupTests(test);

 let stubConfig: Config;

 test.beforeEach(() => {
-  initializeEnvironment("1.2.3");
+  getEnv().initialise("1.2.3");

  stubConfig = createTestConfig({
    languages: [BuiltInLanguage.cpp],
@@ -127,6 +126,19 @@ function mockReleaseApi({
    });
 }

+function mockApiDetails(apiDetails: Required<GitHubApiDetails>) {
+  // This is a workaround to mock `api.getApiDetails()` since it doesn't seem to be possible to
+  // mock this directly. The difficulty is that `getApiDetails()` is called locally in
+  // `api-client.ts`, but `sinon.stub(api, "getApiDetails")` only affects calls to
+  // `getApiDetails()` via an imported `api` module.
+  sinon
+    .stub(actionsUtil, "getRequiredInput")
+    .withArgs("token")
+    .returns(apiDetails.auth);
+  process.env["GITHUB_SERVER_URL"] = apiDetails.url;
+  process.env["GITHUB_API_URL"] = apiDetails.apiURL || "";
+}
+
 async function stubCodeql(): Promise<codeql.CodeQL> {
  const codeqlObject = await codeql.getCodeQLForTesting();
  sinon.stub(codeqlObject, "getVersion").resolves(makeVersionInfo("2.17.6"));
@@ -278,7 +290,6 @@ for (const { cliVersion, tagName, expectedToolcacheVersion } of [
    async (t) => {
      await util.withTmpDir(async (tmpDir) => {
        setupActionsVars(tmpDir, tmpDir);
-        mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);

        const result = await installIntoToolcache({
          cliVersion,
@@ -459,7 +470,6 @@ test.serial(

    await util.withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);

      await installIntoToolcache({
        tagName: "codeql-bundle-20200601",
@@ -507,7 +517,6 @@ test.serial(

    await util.withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);

      await installIntoToolcache({
        tagName: "codeql-bundle-20200601",
--- a/src/codeql.ts
+++ b/src/codeql.ts
@@ -4,6 +4,7 @@ import * as path from "path";
 import * as core from "@actions/core";
 import * as toolrunner from "@actions/exec/lib/toolrunner";
 import * as yaml from "js-yaml";
+import * as semver from "semver";

 import {
  CommandInvocationError,
@@ -19,6 +20,7 @@ import type { ActionConfig } from "./config/action-config";
 import { appendExtraQueryExclusions, type Config } from "./config-utils";
 import { DocUrl } from "./doc-url";
 import { EnvVar, getEnv, exportEnvVar } from "./environment";
+import { getErrorMessage, isDiskConfigurationError } from "./errors";
 import {
  CodeQLDefaultVersionInfo,
  Feature,
@@ -34,7 +36,9 @@ import { ToolsDownloadStatusReport } from "./tools-download";
 import { ToolsFeature, isSupportedToolsFeature } from "./tools-features";
 import { shouldEnableIndirectTracing } from "./tracer-config";
 import * as util from "./util";
-import { BuildMode, CleanupLevel, getErrorMessage } from "./util";
+import { BuildMode, CleanupLevel } from "./util";
+
+export { isDiskConfigurationError } from "./errors";

 type Options = Array<string | number | boolean>;

@@ -70,6 +74,11 @@ export interface CodeQL {
   * Get a string containing the semver version of the CodeQL executable.
   */
  getVersion(): Promise<VersionInfo>;
+  /**
+   * Determines whether the CLI installation represented by this {@link CodeQL} instance
+   * has at least the {@link requiredVersion}.
+   */
+  isVersionAtLeast(requiredVersion: string): Promise<boolean>;
  /**
   * Print version information about CodeQL.
   */
@@ -274,26 +283,6 @@ const GHES_MOST_RECENT_DEPRECATION_DATE = "2026-09-24";
 /** The CLI verbosity level to use for extraction in debug mode. */
 const EXTRACTION_DEBUG_MODE_VERBOSITY = "progress++";

-/**
- * Decides whether `e` is a disk-related error outside of our control
- * that should be classified as a `ConfigurationError`.
- *
- * @param e The error to check.
- * @returns True if the error should be treated as a `ConfigurationError` or false if not.
- */
-export function isDiskConfigurationError(e: unknown): boolean {
-  if (!(e instanceof Error)) {
-    return false;
-  }
-
-  return (
-    // out of disk space
-    e.message.includes("ENOSPC") ||
-    // access denied
-    e.message.includes("EACCES")
-  );
-}
-
 /**
 * Set up CodeQL CLI access.
 *
@@ -431,6 +420,19 @@ export function createStubCodeQL(partialCodeql: Partial<CodeQL>): CodeQL {
    getVersion: resolveFunction(partialCodeql, "getVersion", async () => ({
      version: "1.0.0",
    })),
+    isVersionAtLeast: resolveFunction(
+      partialCodeql,
+      "codeQlVersionAtLeast",
+      async (requiredVersion) => {
+        return (
+          !!partialCodeql.getVersion &&
+          semver.gte(
+            (await partialCodeql.getVersion()).version,
+            requiredVersion,
+          )
+        );
+      },
+    ),
    printVersion: resolveFunction(partialCodeql, "printVersion"),
    supportsFeature: resolveFunction(
      partialCodeql,
@@ -534,6 +536,9 @@ async function getCodeQLForCmd(
      }
      return result;
    },
+    async isVersionAtLeast(requiredVersion: string) {
+      return semver.gte((await this.getVersion()).version, requiredVersion);
+    },
    async printVersion() {
      // Reuse the cached version information rather than invoking the CLI again.
      core.info(JSON.stringify(await this.getVersion(), null, 2));
@@ -1028,7 +1033,7 @@ async function getCodeQLForCmd(
  // CodeQL object is created.
  if (
    checkVersion &&
-    !(await util.codeQlVersionAtLeast(codeql, CODEQL_MINIMUM_VERSION))
+    !(await codeql.isVersionAtLeast(CODEQL_MINIMUM_VERSION))
  ) {
    throw new util.ConfigurationError(
      `Expected a CodeQL CLI with version at least ${CODEQL_MINIMUM_VERSION} but got version ${
@@ -1038,7 +1043,7 @@ async function getCodeQLForCmd(
  } else if (
    checkVersion &&
    process.env[EnvVar.SUPPRESS_DEPRECATED_SOON_WARNING] !== "true" &&
-    !(await util.codeQlVersionAtLeast(codeql, CODEQL_NEXT_MINIMUM_VERSION))
+    !(await codeql.isVersionAtLeast(CODEQL_NEXT_MINIMUM_VERSION))
  ) {
    const result = await codeql.getVersion();
    core.warning(
--- a/src/config-utils.ts
+++ b/src/config-utils.ts
@@ -82,7 +82,6 @@ import {
  GitHubVersion,
  ConfigurationError,
  BuildMode,
-  codeQlVersionAtLeast,
  cloneObject,
  isDefined,
  checkDiskUsage,
@@ -652,10 +651,7 @@ async function runnerHasSufficientMemory(
  logger: Logger,
 ): Promise<boolean> {
  if (
-    await codeQlVersionAtLeast(
-      codeql,
-      CODEQL_VERSION_REDUCED_OVERLAY_MEMORY_USAGE,
-    )
+    await codeql.isVersionAtLeast(CODEQL_VERSION_REDUCED_OVERLAY_MEMORY_USAGE)
  ) {
    logger.debug(
      `Skipping memory check for overlay analysis because CodeQL version is at least ${CODEQL_VERSION_REDUCED_OVERLAY_MEMORY_USAGE}.`,
@@ -899,7 +895,7 @@ async function validateOverlayDatabaseMode(
    );
    return new Failure(OverlayDisabledReason.IncompatibleBuildMode);
  }
-  if (!(await codeQlVersionAtLeast(codeql, CODEQL_OVERLAY_MINIMUM_VERSION))) {
+  if (!(await codeql.isVersionAtLeast(CODEQL_OVERLAY_MINIMUM_VERSION))) {
    logger.warning(
      `Cannot build an ${overlayDatabaseMode} database because ` +
        `the CodeQL CLI is older than ${CODEQL_OVERLAY_MINIMUM_VERSION}. ` +
--- a/src/database-upload.test.ts
+++ b/src/database-upload.test.ts
@@ -15,6 +15,7 @@ import {
  cleanupAndUploadDatabases,
  uploadBundledDatabase,
 } from "./database-upload";
+import { getEnv } from "./environment";
 import { Feature } from "./feature-flags";
 import * as gitUtils from "./git-utils";
 import { BuiltInLanguage } from "./languages";
@@ -31,18 +32,12 @@ import {
  setupActionsVars,
  setupTests,
 } from "./testing-utils";
-import {
-  CleanupLevel,
-  GitHubVariant,
-  HTTPError,
-  initializeEnvironment,
-  withTmpDir,
-} from "./util";
+import { CleanupLevel, GitHubVariant, HTTPError, withTmpDir } from "./util";

 setupTests(test);

 test.beforeEach(() => {
-  initializeEnvironment("1.2.3");
+  getEnv().initialise("1.2.3");
 });

 const testRepoName: RepositoryNwo = { owner: "github", repo: "example" };
@@ -599,7 +594,6 @@ test.serial(
      const nwo: RepositoryNwo = { owner: "test", repo: "foo" };
      const language: BuiltInLanguage = BuiltInLanguage.java;

-      const env = getTestEnv();
      await t.notThrowsAsync(async () => {
        await uploadBundledDatabase(
          nwo,
@@ -608,14 +602,11 @@ test.serial(
          dbPath,
          content.length,
          SAMPLE_DOTCOM_API_DETAILS,
-          env,
        );
      });

      // Check that our stubs were called and that they received the expected arguments.
      t.is(getApiClient.callCount, 1);
-      t.deepEqual(getApiClient.args[0], [env, SAMPLE_DOTCOM_API_DETAILS]);
-
      t.is(fetchStub.callCount, 1);

      const args = fetchStub.args[0];
--- a/src/database-upload.ts
+++ b/src/database-upload.ts
@@ -10,7 +10,6 @@ import {
 } from "./api-client";
 import { type CodeQL } from "./codeql";
 import { Config } from "./config-utils";
-import type { ReadOnlyEnv } from "./environment";
 import { Feature } from "./feature-flags";
 import * as gitUtils from "./git-utils";
 import { parseGitHubUrl } from "./github";
@@ -267,12 +266,11 @@ export async function uploadBundledDatabase(
  bundledDb: string,
  bundledDbSize: number,
  apiDetails: GitHubApiDetails,
-  env: ReadOnlyEnv = util.getEnv(),
 ): Promise<number> {
-  // It is important that the `apiDetails` that `getApiClient` uses match the ones we were given,
-  // because we use `apiDetails.url` below to construct the URL to upload the database to. That
-  // URL will be specific to the GitHub instance given by `apiDetails` and so the client must match it.
-  const client = getApiClient(env, apiDetails);
+  // Ensure that the `apiDetails` that `getApiClient` uses match the ones we were given here,
+  // because we use `apiDetails.auth` below which must be used with the same instance that
+  // `apiDetails` refers to.
+  const client = getApiClient(util.getEnv(), apiDetails);

  const uploadsUrl = new URL(parseGitHubUrl(apiDetails.url));
  uploadsUrl.hostname = `uploads.${uploadsUrl.hostname}`;
--- a/src/environment.ts
+++ b/src/environment.ts
@@ -281,8 +281,8 @@ export function getOptionalEnvVar(paramName: string): string | undefined {
 * in tests, while clearly signalling in regular code that the consumer of the `ReadOnlyEnv` instance
 * will only read from it.
 */
-export class ReadOnlyEnv<T extends string | undefined = string | undefined> {
-  constructor(protected readonly vars: Record<string, T>) {}
+export class ReadOnlyEnv {
+  constructor(protected readonly vars: Record<string, string | undefined>) {}

  /** Clones the object while detaching the underlying environment from the original. */
  public clone(): this {
@@ -290,7 +290,7 @@ export class ReadOnlyEnv<T extends string | undefined = string | undefined> {
  }

  /** Gets a copy of the underlying environment. */
-  public get(): Record<string, T> {
+  public get(): Record<string, string | undefined> {
    return { ...this.vars };
  }

@@ -305,7 +305,7 @@ export class ReadOnlyEnv<T extends string | undefined = string | undefined> {
  }

  /** Gets the entries of the underlying `ProcessEnv`. */
-  public entries(): Array<[string, T]> {
+  public entries(): Array<[string, string | undefined]> {
    return Object.entries(this.vars);
  }

@@ -335,19 +335,17 @@ export class ReadOnlyEnv<T extends string | undefined = string | undefined> {
 * Use `ReadOnlyEnv` instead if you only plan to read from the environment.
 * This type allows writing to the environment.
 */
-export class Env<
-  T extends string | undefined = string | undefined,
-> extends ReadOnlyEnv<T> {
+export class Env extends ReadOnlyEnv {
  private changed: boolean = false;

  /** Sets an environment variable. */
-  public set(name: string, value: T): void {
+  public set(name: string, value: string): void {
    this.vars[name] = value;
    this.changed = true;
  }

  /** Sets all environment variables given by `vars`. */
-  public setAll(vars: Record<string, T>): void {
+  public setAll(vars: Record<string, string>): void {
    for (const [key, val] of Object.entries(vars)) {
      this.set(key, val);
    }
@@ -361,7 +359,7 @@ export class Env<
   * @param name The name of the environment variable to set and export.
   * @param val The value to set and export for the environment variable.
   */
-  public export(name: string, val: T): void {
+  public export(name: string, val: string): void {
    // Setting the environment variable for this instance is always OK, including
    // in tests, since we use fresh `Env` instances whenever needed. This allows
    // tests to pass that rely on that part of the `core.exportVariable` behaviour.
@@ -373,6 +371,18 @@ export class Env<
    }
  }

+  /**
+   * Set some initial environment variables that we can set even without
+   * knowing what version of CodeQL we're running.
+   */
+  public initialise(version: string) {
+    this.export(EnvVar.FEATURE_MULTI_LANGUAGE, "false");
+    this.export(EnvVar.FEATURE_SANDWICH, "false");
+    this.export(EnvVar.FEATURE_SARIF_COMBINE, "true");
+    this.export(EnvVar.FEATURE_WILL_UPLOAD, "true");
+    this.export(EnvVar.VERSION, version);
+  }
+
  /** Gets a value indicating whether `set` was called at least once. */
  public hasChanged(): boolean {
    return this.changed;
--- a/src/errors/index.ts
+++ b/src/errors/index.ts
@@ -0,0 +1,73 @@
+import * as json from "../json";
+
+/**
+ * If {@link error} is not already an instance of {@link Error}, then this function constructs
+ * an {@link Error} with a string representation of {@link error} as the message.
+ */
+export function wrapError(error: unknown): Error {
+  return error instanceof Error ? error : new Error(String(error));
+}
+
+/**
+ * Returns an appropriate message for the error.
+ *
+ * If the error is an {@link Error} instance, this returns the error message without
+ * an `Error: ` prefix.
+ */
+export function getErrorMessage(error: unknown): string {
+  return error instanceof Error ? error.message : String(error);
+}
+
+/**
+ * Decides whether `e` is a disk-related error outside of our control
+ * that should be classified as a `ConfigurationError`.
+ *
+ * @param e The error to check.
+ * @returns True if the error should be treated as a `ConfigurationError` or false if not.
+ */
+export function isDiskConfigurationError(e: unknown): boolean {
+  if (!(e instanceof Error)) {
+    return false;
+  }
+
+  return (
+    // out of disk space
+    e.message.includes("ENOSPC") ||
+    // access denied
+    e.message.includes("EACCES")
+  );
+}
+
+/**
+ * An Error class that indicates an error that occurred due to
+ * a misconfiguration of the action or the CodeQL CLI.
+ */
+export class ConfigurationError extends Error {}
+
+/** Minimal representation of errors resulting from HTTP requests. */
+export class HTTPError extends Error {
+  public status: number;
+
+  constructor(message: string, status: number) {
+    super(message);
+    this.status = status;
+  }
+}
+
+/**
+ * Tries to convert {@link arg} to a {@link HTTPError}, but returns `undefined` if
+ * {@link arg} is not like a {@link HTTPError}.
+ */
+export function asHTTPError(arg: any): HTTPError | undefined {
+  if (!json.isObject<any>(arg) || !json.isString(arg.message)) {
+    return undefined;
+  }
+  if (Number.isInteger(arg.status)) {
+    return new HTTPError(arg.message, arg.status as number);
+  }
+  // See https://github.com/actions/toolkit/blob/acb230b99a46ed33a3f04a758cd68b47b9a82908/packages/tool-cache/src/tool-cache.ts#L19
+  if (Number.isInteger(arg.httpStatusCode)) {
+    return new HTTPError(arg.message, arg.httpStatusCode as number);
+  }
+  return undefined;
+}
--- a/src/feature-flags.test.ts
+++ b/src/feature-flags.test.ts
@@ -4,6 +4,7 @@ import * as path from "path";
 import test from "ava";

 import * as defaults from "./defaults.json";
+import { getEnv } from "./environment";
 import {
  Feature,
  featureConfig,
@@ -26,12 +27,12 @@ import {
  setupTests,
  stubFeatureFlagApiEndpoint,
 } from "./testing-utils";
-import { GitHubVariant, initializeEnvironment, withTmpDir } from "./util";
+import { GitHubVariant, withTmpDir } from "./util";

 setupTests(test);

 test.beforeEach(() => {
-  initializeEnvironment("1.2.3");
+  getEnv().initialise("1.2.3");
 });

 test.serial(
--- a/src/feature-flags.ts
+++ b/src/feature-flags.ts
@@ -74,11 +74,6 @@ export enum Feature {
  AllowMergeConfigFiles = "allow_merge_config_files",
  /** Controls whether we allow multiple values for the `analysis-kinds` input. */
  AllowMultipleAnalysisKinds = "allow_multiple_analysis_kinds",
-  /**
-   * Controls whether we delete CodeQL bundles that we are not going to use from the toolcache
-   * before downloading a different bundle, in order to reclaim disk space.
-   */
-  CleanupToolcacheBundles = "cleanup_toolcache_bundles",
  CleanupTrapCaches = "cleanup_trap_caches",
  /** Whether to allow the `config-file` input to be specified via a repository property. */
  ConfigFileRepositoryProperty = "config_file_repository_property",
@@ -221,11 +216,6 @@ export const featureConfig = {
    envVar: "CODEQL_ACTION_ALLOW_MULTIPLE_ANALYSIS_KINDS",
    minimumVersion: undefined,
  },
-  [Feature.CleanupToolcacheBundles]: {
-    defaultValue: false,
-    envVar: "CODEQL_ACTION_CLEANUP_TOOLCACHE_BUNDLES",
-    minimumVersion: undefined,
-  },
  [Feature.CleanupTrapCaches]: {
    defaultValue: false,
    envVar: "CODEQL_ACTION_CLEANUP_TRAP_CACHES",
@@ -599,7 +589,7 @@ class OfflineFeatures implements FeatureEnablement {
    // Never use this feature if the CLI version explicitly can't support it.
    const minimumVersion = config.minimumVersion;
    if (codeql && minimumVersion) {
-      if (!(await util.codeQlVersionAtLeast(codeql, minimumVersion))) {
+      if (!(await codeql.isVersionAtLeast(minimumVersion))) {
        this.logger.debug(
          `Feature ${feature} is disabled because the CodeQL CLI version is older than the minimum ` +
            `version ${minimumVersion}.`,
--- a/src/feature-flags/offline-features.test.ts
+++ b/src/feature-flags/offline-features.test.ts
@@ -8,7 +8,7 @@ import {
  LoggedMessage,
  setupTests,
 } from "../testing-utils";
-import { GitHubVariant, initializeEnvironment, withTmpDir } from "../util";
+import { getEnv, GitHubVariant, withTmpDir } from "../util";

 import {
  assertAllFeaturesHaveDefaultValues,
@@ -18,7 +18,7 @@ import {
 setupTests(test);

 test.beforeEach(() => {
-  initializeEnvironment("1.2.3");
+  getEnv().initialise("1.2.3");
 });

 test("OfflineFeatures makes no API requests", async (t) => {
--- a/src/github.ts
+++ b/src/github.ts
@@ -1,5 +1,19 @@
 import { ActionsEnvVars, type ReadOnlyEnv } from "./environment";
-import { ConfigurationError } from "./util";
+import { ConfigurationError } from "./errors";
+
+export enum GitHubVariant {
+  /** [GitHub.com](https://github.com) */
+  DOTCOM = "GitHub.com",
+  /** [GitHub Enterprise Server](https://docs.github.com/en/enterprise-server@latest/admin/overview/about-github-enterprise-server) */
+  GHES = "GitHub Enterprise Server",
+  /** [GitHub Enterprise Cloud with data residency](https://docs.github.com/en/enterprise-cloud@latest/admin/data-residency/about-github-enterprise-cloud-with-data-residency) */
+  GHEC_DR = "GitHub Enterprise Cloud with data residency",
+}
+
+export type GitHubVersion =
+  | { type: GitHubVariant.DOTCOM }
+  | { type: GitHubVariant.GHEC_DR }
+  | { type: GitHubVariant.GHES; version: string };

 /** A string representing a GitHub instance address. */
 export type InstanceURL = string;
--- a/src/init-action.ts
+++ b/src/init-action.ts
@@ -88,12 +88,10 @@ import {
  checkDiskUsage,
  checkForTimeout,
  checkGitHubVersionInRange,
-  codeQlVersionAtLeast,
  DEFAULT_DEBUG_ARTIFACT_NAME,
  DEFAULT_DEBUG_DATABASE_NAME,
  getCodeQLMemoryLimit,
  getThreadsFlagValue,
-  initializeEnvironment,
  ConfigurationError,
  wrapError,
  checkActionVersion,
@@ -226,7 +224,7 @@ async function run(
  let toolsVersion: string;

  try {
-    initializeEnvironment(getActionVersion());
+    actionState.env.initialise(getActionVersion());

    // Make inputs accessible in the `post` step.
    persistInputs();
@@ -686,7 +684,7 @@ async function run(
        `${EnvVar.JAVA_EXTRACTOR_MINIMIZE_DEPENDENCY_JARS} is already set to '${process.env[EnvVar.JAVA_EXTRACTOR_MINIMIZE_DEPENDENCY_JARS]}', so the Action will not override it.`,
      );
    } else if (
-      (await codeQlVersionAtLeast(codeql, CODEQL_VERSION_JAR_MINIMIZATION)) &&
+      (await codeql.isVersionAtLeast(CODEQL_VERSION_JAR_MINIMIZATION)) &&
      config.dependencyCachingEnabled &&
      config.buildMode === BuildMode.None &&
      config.languages.includes(BuiltInLanguage.java)
--- a/src/setup-codeql-action.ts
+++ b/src/setup-codeql-action.ts
@@ -38,7 +38,6 @@ import {
  checkDiskUsage,
  checkForTimeout,
  checkGitHubVersionInRange,
-  initializeEnvironment,
  ConfigurationError,
  wrapError,
  checkActionVersion,
@@ -108,7 +107,7 @@ async function run(
  let toolsVersion: string;

  try {
-    initializeEnvironment(getActionVersion());
+    actionState.env.initialise(getActionVersion());

    const apiDetails = {
      auth: getRequiredInput("token"),
--- a/src/setup-codeql.test.ts
+++ b/src/setup-codeql.test.ts
@@ -11,7 +11,13 @@ import * as sinon from "sinon";
 import * as actionsUtil from "./actions-util";
 import * as api from "./api-client";
 import * as diagnostics from "./diagnostics";
-import { ActionsEnvVars, Env, EnvVar, ReadOnlyEnv } from "./environment";
+import {
+  ActionsEnvVars,
+  Env,
+  EnvVar,
+  getEnv,
+  ReadOnlyEnv,
+} from "./environment";
 import { Feature } from "./feature-flags";
 import { BuiltInLanguage } from "./languages";
 import { getRunnerLogger } from "./logging";
@@ -32,24 +38,17 @@ import {
  getTestEnv,
  initAllState,
  makeMacro,
-  mockApiDetails,
  mockBundleDownloadApi,
  setupActionsVars,
  setupTests,
 } from "./testing-utils";
 import * as toolsDownload from "./tools-download";
-import {
-  getErrorMessage,
-  GitHubVariant,
-  HTTPError,
-  initializeEnvironment,
-  withTmpDir,
-} from "./util";
+import { getErrorMessage, GitHubVariant, HTTPError, withTmpDir } from "./util";

 setupTests(test);

 test.beforeEach(() => {
-  initializeEnvironment("1.2.3");
+  getEnv().initialise("1.2.3");
 });

 function stubDownloadAndExtract() {
@@ -156,7 +155,6 @@ test.serial(
        compressionMethod: "gzip",
        sourceType: "download",
        toolsVersion: "1.2.3",
-        apiDetails: SAMPLE_DOTCOM_API_DETAILS,
      } satisfies setupCodeql.CodeQLDownloadSource);
    });
  },
@@ -223,7 +221,6 @@ for (const {

      await withTmpDir(async (tmpDir) => {
        setupActionsVars(tmpDir, tmpDir);
-        mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
        const source = await setupCodeql.getCodeQLSource(
          "linked",
          SAMPLE_DEFAULT_CLI_VERSION,
@@ -258,7 +255,6 @@ test.serial(

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
      const source = await setupCodeql.getCodeQLSource(
        "latest",
        SAMPLE_DEFAULT_CLI_VERSION,
@@ -302,7 +298,6 @@ test.serial(

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
      const result = await setupCodeql.setupCodeQLBundle(
        "linked",
        SAMPLE_DOTCOM_API_DETAILS,
@@ -436,7 +431,6 @@ test.serial(
        compressionMethod: "zstd",
        sourceType: "download",
        toolsVersion: expectedVersion,
-        apiDetails: SAMPLE_DOTCOM_API_DETAILS,
      } satisfies setupCodeql.CodeQLToolsSource);

      const result = await setupCodeql.setupCodeQLBundle(
@@ -485,7 +479,6 @@ test.serial(

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir, { GITHUB_EVENT_NAME: "dynamic" });
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);

      const source = await setupCodeql.getCodeQLSource(
        undefined,
@@ -510,7 +503,6 @@ test.serial(
        compressionMethod: "zstd",
        sourceType: "download",
        toolsVersion: expectedVersion,
-        apiDetails: SAMPLE_DOTCOM_API_DETAILS,
      } satisfies setupCodeql.CodeQLToolsSource);

      // Afterwards, ensure that we see the expected messages in the log.
@@ -604,7 +596,7 @@ test.serial(
        undefined, // rawLanguages
        undefined, // otherLanguagePacksReason
        false, // useOverlayAwareDefaultCliVersion
-        createFeatures([Feature.CleanupToolcacheBundles]),
+        createFeatures([]),
        getRunnerLogger(true),
      );

@@ -632,7 +624,6 @@ for (const toolsInput of ["nightly", "nightly-latest"]) {

      await withTmpDir(async (tmpDir) => {
        setupActionsVars(tmpDir, tmpDir);
-        mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
        const source = await setupCodeql.getCodeQLSource(
          toolsInput,
          SAMPLE_DEFAULT_CLI_VERSION,
@@ -658,7 +649,6 @@ for (const toolsInput of ["nightly", "nightly-latest"]) {
          cliVersion: undefined,
          compressionMethod: "zstd",
          toolsVersion: "0.0.0-30260213",
-          apiDetails: SAMPLE_DOTCOM_API_DETAILS,
        } satisfies setupCodeql.CodeQLDownloadSource);
        t.true(latestNightlyRequest.calledOnce);
      });
@@ -811,7 +801,6 @@ for (const date of ["20200101", "30260213"]) {
            cliVersion: undefined,
            compressionMethod: "zstd",
            toolsVersion: `0.0.0-${date}`,
-            apiDetails: SAMPLE_DOTCOM_API_DETAILS,
          } satisfies setupCodeql.CodeQLDownloadSource);

          await t.throwsAsync(
@@ -956,7 +945,6 @@ const toolcacheInputFallbackMacro = makeMacro({

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);

      for (const [k, v] of Object.entries(environment)) {
        process.env[k] = v;
@@ -1177,7 +1165,6 @@ test.serial(

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
      const source = await setupCodeql.getCodeQLSource(
        undefined,
        PER_LANGUAGE_CLI_VERSION,
@@ -1220,7 +1207,6 @@ test.serial(

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
      for (const { otherLanguagePacksReason, features } of [
        // The per-language feature is disabled.
        { otherLanguagePacksReason: undefined, features: createFeatures([]) },
@@ -1290,14 +1276,7 @@ for (const fallback of [false, true]) {
        request: { fetch: fetchRelease },
      });
      sinon.stub(api, "getApiClient").value(() => client);
-
-      const spyClient = new api.InstanceApiClient(SAMPLE_DOTCOM_API_DETAILS);
-      const authorizationSpy = sinon.spy(
-        spyClient,
-        "getAuthorizationHeaderFor",
-      );
-      sinon.stub(api, "InstanceApiClient").returns(spyClient);
-
+      const authorizationSpy = sinon.spy(api, "getAuthorizationHeaderFor");
      const extractStub = stubDownloadAndExtract();
      if (fallback) {
        extractStub.onFirstCall().rejects(new HTTPError("Not Found", 404));
@@ -1307,7 +1286,6 @@ for (const fallback of [false, true]) {
        setupActionsVars(tmpDir, tmpDir, {
          GITHUB_ACTION_REPOSITORY: "codeql-testing/action-fork",
        });
-        mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
        const result = await setupCodeql.setupCodeQLBundle(
          undefined,
          SAMPLE_DOTCOM_API_DETAILS,
@@ -1330,9 +1308,9 @@ for (const fallback of [false, true]) {
        t.is(extractStub.firstCall.args[0], assetURL);
        t.is(extractStub.lastCall.args[0], fallback ? combinedURL : assetURL);
        t.is(authorizationSpy.callCount, extractStub.callCount);
-        t.is(authorizationSpy.firstCall.args[1], assetURL);
+        t.is(authorizationSpy.firstCall.args[2], assetURL);
        t.is(
-          authorizationSpy.lastCall.args[1],
+          authorizationSpy.lastCall.args[2],
          fallback ? combinedURL : assetURL,
        );
        t.is(extractStub.lastCall.args[3], "token token");
@@ -1397,10 +1375,7 @@ for (const bundle of ["per-language", "combined", "fallback"] as const) {
          };
        });
      const addDiagnostic = sinon.stub(diagnostics, "addNoLanguageDiagnostic");
-      const features = createFeatures([
-        Feature.PerLanguageBundles,
-        Feature.CleanupToolcacheBundles,
-      ]);
+      const features = createFeatures([Feature.PerLanguageBundles]);

      await withTmpDir(async (tmpDir) => {
        setupActionsVars(tmpDir, tmpDir);
@@ -1575,7 +1550,6 @@ for (const error of [

      await withTmpDir(async (tmpDir) => {
        setupActionsVars(tmpDir, tmpDir);
-        mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
        await t.throwsAsync(
          setupCodeql.setupCodeQLBundle(
            undefined,
@@ -1849,11 +1823,15 @@ function createToolcacheEntry(
 */
 async function runDownloadCodeQL(
  toolcacheRoot: string,
-  features: Feature[],
  bundleVersion: string | undefined,
-  env = getTestEnv({
-    [ActionsEnvVars.RUNNER_TOOL_CACHE]: toolcacheRoot,
-  }),
+  {
+    env = getTestEnv({
+      [ActionsEnvVars.RUNNER_ENVIRONMENT]: "github-hosted",
+      [ActionsEnvVars.RUNNER_TOOL_CACHE]: toolcacheRoot,
+    }),
+  }: {
+    env?: Env;
+  } = {},
 ): Promise<{
  codeqlFolder: string;
  cleanupDiagnostic: toolsDownload.ToolcacheCleanupResult | undefined;
@@ -1864,7 +1842,6 @@ async function runDownloadCodeQL(
  const { codeqlFolder } = await setupCodeql.downloadCodeQLBundle(
    initAllState({
      env,
-      features: createFeatures(features),
    }),
    {
      bundle: {
@@ -1876,8 +1853,8 @@ async function runDownloadCodeQL(
      cliVersion: CLEANUP_CLI_VERSION,
      sourceType: "download",
      toolsVersion: CLEANUP_CLI_VERSION,
-      apiDetails: SAMPLE_DOTCOM_API_DETAILS,
    },
+    SAMPLE_DOTCOM_API_DETAILS,
    undefined, // tarVersion
    toolcacheRoot, // tempDir
  );
@@ -1902,11 +1879,9 @@ async function runDownloadCodeQL(
 async function testToolcacheCleanup(
  t: ExecutionContext<unknown>,
  {
-    features,
    runnerEnvironment,
    setUp,
  }: {
-    features: Feature[];
    runnerEnvironment: string | undefined;
    setUp?: (env: Env) => void;
  },
@@ -1918,12 +1893,8 @@ async function testToolcacheCleanup(
 ) {
  await withTmpDir(async (tmpDir) => {
    setupActionsVars(tmpDir, tmpDir);
-    if (runnerEnvironment === undefined) {
-      delete process.env[ActionsEnvVars.RUNNER_ENVIRONMENT];
-    } else {
-      process.env[ActionsEnvVars.RUNNER_ENVIRONMENT] = runnerEnvironment;
-    }
    const env = getTestEnv({
+      [ActionsEnvVars.RUNNER_ENVIRONMENT]: runnerEnvironment,
      [ActionsEnvVars.RUNNER_TOOL_CACHE]: tmpDir,
    });
    setUp?.(env);
@@ -1943,9 +1914,8 @@ async function testToolcacheCleanup(

    const { cleanupDiagnostic } = await runDownloadCodeQL(
      tmpDir,
-      features,
      CLEANUP_BUNDLE_VERSION,
-      env,
+      { env },
    );

    t.true(
@@ -1957,28 +1927,12 @@ async function testToolcacheCleanup(
  });
 }

-test.serial(
-  "downloadCodeQLBundle does not clean up the toolcache when the feature flag is disabled",
-  async (t) => {
-    await testToolcacheCleanup(
-      t,
-      { features: [], runnerEnvironment: "github-hosted" },
-      ({ cleanupDiagnostic, destinationDirectory, staleDirectory }) => {
-        t.true(fs.existsSync(staleDirectory));
-        t.true(fs.existsSync(destinationDirectory));
-        t.is(cleanupDiagnostic, undefined);
-      },
-    );
-  },
-);
-
 test.serial(
  "downloadCodeQLBundle does not clean up the toolcache when the runner is not GitHub-hosted",
  async (t) => {
    await testToolcacheCleanup(
      t,
      {
-        features: [Feature.CleanupToolcacheBundles],
        runnerEnvironment: "self-hosted",
      },
      ({ cleanupDiagnostic, destinationDirectory, staleDirectory }) => {
@@ -1998,7 +1952,6 @@ test.serial(
    await testToolcacheCleanup(
      t,
      {
-        features: [Feature.CleanupToolcacheBundles],
        runnerEnvironment: undefined,
      },
      ({ cleanupDiagnostic, destinationDirectory, staleDirectory }) => {
@@ -2011,12 +1964,11 @@ test.serial(
 );

 test.serial(
-  "downloadCodeQLBundle deletes other CodeQL bundles from the toolcache when enabled on a GitHub-hosted runner",
+  "downloadCodeQLBundle deletes other CodeQL bundles from the toolcache on a GitHub-hosted runner",
  async (t) => {
    await testToolcacheCleanup(
      t,
      {
-        features: [Feature.CleanupToolcacheBundles],
        runnerEnvironment: "github-hosted",
      },
      ({ cleanupDiagnostic, destinationDirectory, staleDirectory }) => {
@@ -2050,7 +2002,6 @@ test.serial(

      const { cleanupDiagnostic } = await runDownloadCodeQL(
        tmpDir,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
      );

@@ -2080,7 +2031,6 @@ test.serial(

      const { cleanupDiagnostic } = await runDownloadCodeQL(
        tmpDir,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
      );

@@ -2212,7 +2162,6 @@ test.serial(

      const { cleanupDiagnostic } = await runDownloadCodeQL(
        toolcacheRoot,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
      );

@@ -2235,7 +2184,6 @@ test.serial(
    await testToolcacheCleanup(
      t,
      {
-        features: [Feature.CleanupToolcacheBundles],
        runnerEnvironment: "github-hosted",
        setUp: (env) => {
          env.set(EnvVar.HAS_SET_UP_CODEQL, "true");
@@ -2265,9 +2213,13 @@ test.serial(
      );
      const { codeqlFolder, cleanupDiagnostic } = await runDownloadCodeQL(
        tmpDir,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
-        getTestEnv({ [EnvVar.HAS_SET_UP_CODEQL]: "true" }),
+        {
+          env: getTestEnv({
+            [ActionsEnvVars.RUNNER_ENVIRONMENT]: "github-hosted",
+            [EnvVar.HAS_SET_UP_CODEQL]: "true",
+          }),
+        },
      );

      t.true(fs.existsSync(staleDirectory));
@@ -2282,7 +2234,6 @@ test.serial(
  async (t) => {
    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
      delete process.env[EnvVar.HAS_SET_UP_CODEQL];

      stubDownloadAndExtract();
@@ -2318,7 +2269,6 @@ test.serial(

    await withTmpDir(async (tmpDir) => {
      setupActionsVars(tmpDir, tmpDir);
-      mockApiDetails(SAMPLE_DOTCOM_API_DETAILS);
      process.env[ActionsEnvVars.RUNNER_ENVIRONMENT] = "github-hosted";
      delete process.env[EnvVar.HAS_SET_UP_CODEQL];
      const staleDirectory = createToolcacheEntry(
@@ -2337,7 +2287,7 @@ test.serial(
          undefined, // rawLanguages
          undefined, // otherLanguagePacksReason
          false, // useOverlayAwareDefaultCliVersion
-          createFeatures([Feature.CleanupToolcacheBundles]),
+          createFeatures([]),
          getRunnerLogger(true),
        ),
        { is: error },
@@ -2372,7 +2322,6 @@ test.serial(

      const { codeqlFolder, cleanupDiagnostic } = await runDownloadCodeQL(
        tmpDir,
-        [Feature.CleanupToolcacheBundles],
        undefined, // bundleVersion
      );

@@ -2406,7 +2355,6 @@ test.serial(

      const { cleanupDiagnostic } = await runDownloadCodeQL(
        tmpDir,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
      );

@@ -2442,7 +2390,6 @@ test.serial(

      const { cleanupDiagnostic } = await runDownloadCodeQL(
        tmpDir,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
      );

@@ -2492,7 +2439,6 @@ test.serial(

      const { cleanupDiagnostic } = await runDownloadCodeQL(
        toolcacheRoot,
-        [Feature.CleanupToolcacheBundles],
        CLEANUP_BUNDLE_VERSION,
      );

--- a/src/setup-codeql.ts
+++ b/src/setup-codeql.ts
@@ -718,7 +718,6 @@ export async function getCodeQLSource(
    compressionMethod,
    sourceType: "download",
    toolsVersion: resolvedVersion ?? "unknown",
-    apiDetails,
  };
 }

@@ -747,6 +746,7 @@ async function tryGetFallbackToolcacheVersion(
 // be able to stub this function and have other functions in this file use that stub.
 export const downloadCodeQL = async function (
  source: CodeQLDownloadSource,
+  apiDetails: api.GitHubApiDetails,
  tarVersion: tar.TarVersion | undefined,
  tempDir: string,
  logger: Logger,
@@ -767,8 +767,11 @@ export const downloadCodeQL = async function (
  if (searchParams.has("token")) {
    logger.debug("CodeQL tools URL contains an authorization token.");
  } else {
-    const client = new api.InstanceApiClient(source.apiDetails);
-    authorization = client.getAuthorizationHeaderFor(logger, codeqlURL);
+    authorization = api.getAuthorizationHeaderFor(
+      logger,
+      apiDetails,
+      codeqlURL,
+    );
  }

  const toolcacheDestination = getToolcacheDestination({ logger }, source);
@@ -836,7 +839,7 @@ function getToolcacheDestination(
 }

 /**
- * Reclaims disk space by deleting the CodeQL tools from the toolcache, if enabled.
+ * Reclaims disk space by deleting the CodeQL tools from the toolcache on GitHub-hosted runners.
 *
 * On GitHub-hosted runners the toolcache shares a filesystem with the workspace, so tools left in
 * the toolcache take up space that the analysis could use instead. This holds wherever we extract
@@ -844,9 +847,8 @@ function getToolcacheDestination(
 */
 async function tryDeleteToolcacheBundles({
  env,
-  features,
  logger,
-}: ActionState<["Logger", "ReadOnlyEnv", "FeatureFlags"]>): Promise<void> {
+}: ActionState<["Logger", "ReadOnlyEnv"]>): Promise<void> {
  // A step that has already set up CodeQL may hand out a path into the toolcache that a later step
  // runs, so only the first step to set it up can know that nothing else relies on the toolcache.
  if (env.getOptional(EnvVar.HAS_SET_UP_CODEQL) !== undefined) {
@@ -857,11 +859,7 @@ async function tryDeleteToolcacheBundles({
    return;
  }

-  if (
-    !isGitHubHostedRunner() ||
-    !isToolcacheOnWorkspaceFilesystem(logger) ||
-    !(await features.getValue(Feature.CleanupToolcacheBundles))
-  ) {
+  if (!isGitHubHostedRunner(env) || !isToolcacheOnWorkspaceFilesystem(logger)) {
    return;
  }

@@ -980,8 +978,9 @@ export async function setupCodeQLBundle(
      break;
    case "download": {
      const result = await downloadCodeQLBundle(
-        { env: getEnv(), features, logger },
+        { env: getEnv(), logger },
        source,
+        apiDetails,
        zstdAvailability.version,
        tempDir,
      );
@@ -1015,8 +1014,9 @@ export async function setupCodeQLBundle(
 * @returns The extraction directory and download timings.
 */
 export async function downloadCodeQLBundle(
-  action: ActionState<["Logger", "ReadOnlyEnv", "FeatureFlags"]>,
+  action: ActionState<["Logger", "ReadOnlyEnv"]>,
  source: CodeQLDownloadSource,
+  apiDetails: api.GitHubApiDetails,
  tarVersion: tar.TarVersion | undefined,
  tempDir: string,
 ): Promise<{
@@ -1030,7 +1030,13 @@ export async function downloadCodeQLBundle(

  const startTime = performance.now();
  try {
-    return await downloadCodeQL(source, tarVersion, tempDir, logger);
+    return await downloadCodeQL(
+      source,
+      apiDetails,
+      tarVersion,
+      tempDir,
+      logger,
+    );
  } catch (e) {
    if (
      bundle.kind !== "per-language" ||
@@ -1046,6 +1052,7 @@ export async function downloadCodeQLBundle(
        ...source,
        bundle: { kind: "combined", url: bundle.combinedBundleURL },
      },
+      apiDetails,
      tarVersion,
      tempDir,
      logger,
--- a/src/setup/repository.test.ts
+++ b/src/setup/repository.test.ts
@@ -6,7 +6,6 @@ import * as sinon from "sinon";
 import * as actionsUtil from "../actions-util";
 import { ActionsEnvVars } from "../environment";
 import { callee, getTestEnv, setupTests } from "../testing-utils";
-import { initializeEnvironment } from "../util";

 import { getCodeQLActionRepository } from "./repository";

@@ -16,7 +15,7 @@ test.serial("getCodeQLActionRepository", async (t) => {
  const initialEnv = getTestEnv({
    [ActionsEnvVars.RUNNER_TEMP]: path.dirname(__dirname),
  });
-  initializeEnvironment("1.2.3", initialEnv);
+  initialEnv.initialise("1.2.3");

  const target = callee(getCodeQLActionRepository)
    .withArgs()
--- a/src/setup/repository.ts
+++ b/src/setup/repository.ts
@@ -2,7 +2,7 @@ import { ActionState } from "../action-common";
 import { isRunningLocalAction } from "../actions-util";
 import * as api from "../api-client";
 import { ActionsEnvVars } from "../environment";
-import { GITHUB_DOTCOM_URL } from "../github";
+import { GITHUB_DOTCOM_URL, type InstanceURL } from "../github";
 import {
  isRepositoryNwoStr,
  parseRepositoryNwo,
@@ -47,14 +47,20 @@ export function getCodeQLActionRepository(
 }

 /**A download source is a pair of strings. */
-export type DownloadSource = [api.GitHubApiDetails, RepositoryNwoStr];
+export type DownloadSource = [InstanceURL, RepositoryNwoStr];
+
+/** GitHub.com, and the canonical Action. */
+export const DEFAULT_DOWNLOAD_SOURCE: DownloadSource = [
+  GITHUB_DOTCOM_URL,
+  CODEQL_DEFAULT_ACTION_REPOSITORY,
+];

 /** Decides if the two provided download sources are the same. */
 const isSameDownloadSource = (
-  [srcInstance, srcRepo]: DownloadSource,
-  [otherInstance, otherRepo]: DownloadSource,
+  [srcUrl, srcRepo]: DownloadSource,
+  [otherUrl, otherRepo]: DownloadSource,
 ) => {
-  return srcInstance.url === otherInstance.url && srcRepo === otherRepo;
+  return srcUrl === otherUrl && srcRepo === otherRepo;
 };

 /** A download URL is represented as a string. */
@@ -97,21 +103,13 @@ export async function getCodeQLAssetDownloadURL(
 ): Promise<DownloadURL> {
  const codeQLActionRepository = getCodeQLActionRepository(action);

-  // We construct the default GitHub.com source here, because `getDotcomApiDetails`
-  // may retrieve the `token` input if we are currently running on GitHub.com and
-  // we want to avoid doing that statically.
-  const defaultDownloadSource: DownloadSource = [
-    api.getDotcomApiDetails(action.env),
-    CODEQL_DEFAULT_ACTION_REPOSITORY,
-  ];
-
  const potentialDownloadSources: DownloadSource[] = [
    // This GitHub instance, and this Action.
-    [apiDetails, codeQLActionRepository],
+    [apiDetails.url, codeQLActionRepository],
    // This GitHub instance, and the canonical Action.
-    [apiDetails, CODEQL_DEFAULT_ACTION_REPOSITORY],
+    [apiDetails.url, CODEQL_DEFAULT_ACTION_REPOSITORY],
    // GitHub.com, and the canonical Action.
-    defaultDownloadSource,
+    DEFAULT_DOWNLOAD_SOURCE,
  ];

  // We now filter out any duplicates.
@@ -124,34 +122,34 @@ export async function getCodeQLAssetDownloadURL(
    },
  );

-  for (const [instance, repository] of uniqueDownloadSources) {
+  for (const [instanceURL, repository] of uniqueDownloadSources) {
    // If we've reached the final case, short-circuit the API check since we know the asset exists and is public.
-    if (isSameDownloadSource(defaultDownloadSource, [instance, repository])) {
+    if (
+      isSameDownloadSource(DEFAULT_DOWNLOAD_SOURCE, [instanceURL, repository])
+    ) {
      break;
    }

    const { owner: repositoryOwner, repo: repositoryName } =
      parseRepositoryNwo(repository);
    try {
-      const release = await api
-        .getApiClient(action.env, instance)
-        .rest.repos.getReleaseByTag({
-          owner: repositoryOwner,
-          repo: repositoryName,
-          tag: tagName,
-        });
+      const release = await api.getApiClient().rest.repos.getReleaseByTag({
+        owner: repositoryOwner,
+        repo: repositoryName,
+        tag: tagName,
+      });

      for (const asset of release.data.assets) {
        if (asset.name === assetName) {
          action.logger.info(
-            `Found ${assetKind} ${assetName} in ${repository} on ${instance.apiURL} with URL ${asset.url}.`,
+            `Found ${assetKind} ${assetName} in ${repository} on ${instanceURL} with URL ${asset.url}.`,
          );
          return asset.url;
        }
      }
    } catch (e) {
      action.logger.info(
-        `Looked for ${assetKind} ${assetName} in ${repository} on ${instance.apiURL} but got error ${e}.`,
+        `Looked for ${assetKind} ${assetName} in ${repository} on ${instanceURL} but got error ${e}.`,
      );
    }
  }
--- a/src/start-proxy.test.ts
+++ b/src/start-proxy.test.ts
@@ -8,7 +8,7 @@ import { ActionState } from "./action-common";
 import * as actionsUtil from "./actions-util";
 import * as apiClient from "./api-client";
 import * as defaults from "./defaults.json";
-import { ActionsEnvVars, type Env } from "./environment";
+import { ActionsEnvVars } from "./environment";
 import { setUpFeatureFlagTests } from "./feature-flags/testing-util";
 import { UnvalidatedObject, validateSchema } from "./json";
 import { makeFromSchema } from "./json/testing-util";
@@ -25,7 +25,6 @@ import {
  initAllState,
  makeMacro,
  makeTestToken,
-  mockApiDetails,
  RecordingLogger,
  SAMPLE_DOTCOM_API_DETAILS,
  setupTests,
@@ -614,23 +613,18 @@ test("getProxyPackage - includes platform in name", (t) => {
  }
 });

-function mockGetApiClient(env: Env, endpoints: any) {
-  const getRequiredInput = mockApiDetails(SAMPLE_DOTCOM_API_DETAILS, env);
-  const getApiClient = sinon
-    .stub(apiClient, "getApiClient")
-    // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
-    .returns({ rest: endpoints } as any);
-
-  return { getRequiredInput, getApiClient };
+function mockGetApiClient(endpoints: any) {
+  return (
+    sinon
+      .stub(apiClient, "getApiClient")
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
+      .returns({ rest: endpoints } as any)
+  );
 }

 type ReleaseAssets = Array<{ name: string; url?: string }>;

-function mockGetReleaseByTag(
-  env: Env,
-  expectedTag?: string,
-  assets?: ReleaseAssets,
-) {
+function mockGetReleaseByTag(expectedTag?: string, assets?: ReleaseAssets) {
  const getReleaseByTag =
    assets === undefined
      ? sinon.stub().rejects()
@@ -651,7 +645,7 @@ function mockGetReleaseByTag(

  return {
    getReleaseByTag,
-    ...mockGetApiClient(env, { repos: { getReleaseByTag } }),
+    getApiClient: mockGetApiClient({ repos: { getReleaseByTag } }),
  };
 }

@@ -677,6 +671,7 @@ test.serial(
  "getDownloadUrl logs unknown platforms/arch and defaults to linux64",
  async (t) => {
    const logger = new RecordingLogger();
+    mockGetReleaseByTag();

    await withTmpDir(async (tempDir) => {
      const features = mockOfflineFeatures(tempDir, logger);
@@ -686,7 +681,6 @@ test.serial(
        logger,
        features,
      });
-      mockGetReleaseByTag(state.env);

      // Stub this to always return `true` so we get the default repo for the tests.
      sinon.stub(actionsUtil, "isRunningLocalAction").returns(true);
@@ -716,11 +710,11 @@ test.serial(
  "getDownloadUrl returns default bundle URL for linked version",
  async (t) => {
    const logger = new RecordingLogger();
+    mockGetReleaseByTag();

    await withTmpDir(async (tempDir) => {
      const features = mockOfflineFeatures(tempDir, logger);
      const state = initAllState({ logger, features });
-      mockGetReleaseByTag(state.env);

      // Stub this to always return `true` so we get the default repo for the tests.
      sinon.stub(actionsUtil, "isRunningLocalAction").returns(true);
@@ -756,11 +750,7 @@ test.serial(
      sinon.stub(actionsUtil, "isRunningLocalAction").returns(true);

      for (const assets of testAssets) {
-        const stubs = mockGetReleaseByTag(
-          state.env,
-          defaults.bundleVersion,
-          assets,
-        );
+        const stubs = mockGetReleaseByTag(defaults.bundleVersion, assets);
        const info = await startProxyExports.getDownloadUrl(
          state,
          SAMPLE_DOTCOM_API_DETAILS,
@@ -778,7 +768,6 @@ test.serial(
        // mockGetReleaseByTag stubs the global getApiClient; since we are calling
        // that in a loop, we need to manually restore it here
        stubs.getApiClient.restore();
-        stubs.getRequiredInput.restore();
      }
    });
  },
@@ -794,7 +783,7 @@ test.serial("getDownloadUrl returns matching release asset", async (t) => {
      url: "url-we-want",
    },
  ];
-  const stubs = mockGetReleaseByTag(state.env, defaults.bundleVersion, assets);
+  const stubs = mockGetReleaseByTag(defaults.bundleVersion, assets);

  await withTmpDir(async (tempDir) => {
    state.env.set(ActionsEnvVars.RUNNER_TEMP, tempDir);
@@ -936,8 +925,7 @@ test.serial(
  "getProxyBinaryPath - returns path from tool cache if available",
  async (t) => {
    const logger = new RecordingLogger();
-
-    sinon.stub(apiClient, "getApiDetails").returns(SAMPLE_DOTCOM_API_DETAILS);
+    mockGetReleaseByTag();

    await withTmpDir(async (tempDir) => {
      const toolcachePath = "/path/to/proxy/dir";
@@ -947,11 +935,8 @@ test.serial(
      sinon.stub(actionsUtil, "isRunningLocalAction").returns(true);

      const features = mockOfflineFeatures(tempDir, logger);
-      const state = initAllState({ logger, features });
-      mockGetReleaseByTag(state.env);
-
      const result = await startProxyExports.getProxyBinaryPath(
-        state,
+        initAllState({ logger, features }),
        SAMPLE_DOTCOM_API_DETAILS,
      );

@@ -971,7 +956,7 @@ test.serial(
    const logger = new RecordingLogger();
    const state = initAllState({ logger });
    const downloadUrl = "url-we-want";
-    const stubs = mockGetReleaseByTag(state.env, defaults.bundleVersion, [
+    const stubs = mockGetReleaseByTag(defaults.bundleVersion, [
      {
        name: startProxyExports.getProxyPackage(getTestPlatform(state)),
        url: downloadUrl,
@@ -980,16 +965,9 @@ test.serial(

    const toolcachePath = "/path/to/proxy/dir";
    const find = sinon.stub(toolcache, "find").returns("");
-    const apiDetails = {
-      auth: "",
-      url: "",
-      apiURL: "",
-    } satisfies apiClient.GitHubApiDetails;
-    const client = new apiClient.InstanceApiClient(apiDetails);
    const getAuthorizationHeaderFor = sinon
-      .stub(client, "getAuthorizationHeaderFor")
+      .stub(apiClient, "getAuthorizationHeaderFor")
      .returns(undefined);
-    sinon.stub(apiClient, "InstanceApiClient").returns(client);
    const archivePath = "/path/to/archive";
    const downloadTool = sinon
      .stub(toolcache, "downloadTool")
@@ -1029,7 +1007,7 @@ test.serial(
    t.is(result.version, defaults.cliVersion);

    checkExpectedLogMessages(t, logger.messages, [
-      `Found private registry proxy ${startProxyExports.getProxyPackage(getTestPlatform(state))} in test/repo on https://api.github.com with URL ${downloadUrl}`,
+      `Found private registry proxy ${startProxyExports.getProxyPackage(getTestPlatform(state))} in test/repo on https://github.com with URL ${downloadUrl}`,
    ]);
  },
 );
@@ -1061,21 +1039,14 @@ test.serial(
      headers: {},
      url: "GET /repos/:owner/:repo/releases/tags/:tag",
    });
-    mockGetApiClient(state.env, { repos: { getReleaseByTag } });
+    mockGetApiClient({ repos: { getReleaseByTag } });

    await withTmpDir(async (tempDir) => {
      const toolcachePath = "/path/to/proxy/dir";
      const find = sinon.stub(toolcache, "find").returns("");
-      const apiDetails = {
-        auth: "",
-        url: "",
-        apiURL: "",
-      } satisfies apiClient.GitHubApiDetails;
-      const client = new apiClient.InstanceApiClient(apiDetails);
      const getAuthorizationHeaderFor = sinon
-        .stub(client, "getAuthorizationHeaderFor")
+        .stub(apiClient, "getAuthorizationHeaderFor")
        .returns(undefined);
-      sinon.stub(apiClient, "InstanceApiClient").returns(client);
      const archivePath = "/path/to/archive";
      const downloadTool = sinon
        .stub(toolcache, "downloadTool")
@@ -1136,7 +1107,7 @@ test.serial(
    });

    checkExpectedLogMessages(t, logger.messages, [
-      `Found private registry proxy ${startProxyExports.getProxyPackage(getTestPlatform(state))} in test/repo on https://api.github.com with URL url-we-want.`,
+      `Found private registry proxy ${startProxyExports.getProxyPackage(getTestPlatform(state))} in test/repo on https://github.com with URL url-we-want.`,
    ]);
  },
 );
--- a/src/start-proxy.ts
+++ b/src/start-proxy.ts
@@ -4,9 +4,9 @@ import * as toolcache from "@actions/tool-cache";

 import { ActionState } from "./action-common";
 import {
+  getAuthorizationHeaderFor,
  getGitHubVersion,
-  InstanceApiClient,
-  type GitHubApiDetails,
+  GitHubApiDetails,
 } from "./api-client";
 import * as artifactScanner from "./artifact-scanner";
 import * as defaults from "./defaults.json";
@@ -423,7 +423,6 @@ export async function getProxyBinaryPath(
  logger.startGroup("Setting up authentication proxy");

  try {
-    const client = new InstanceApiClient(apiDetails);
    const proxyFileName = getProxyFilename();
    const proxyInfo = await getDownloadUrl(action, apiDetails);

@@ -438,8 +437,9 @@ export async function getProxyBinaryPath(
        `Authentication proxy is not in the toolcache. Will try to download it from '${proxyInfo.url}'.`,
      );

-      const authorization = client.getAuthorizationHeaderFor(
+      const authorization = getAuthorizationHeaderFor(
        logger,
+        apiDetails,
        proxyInfo.url,
      );
      const temp = await downloadProxy(logger, proxyInfo.url, authorization);
--- a/src/testing-utils.ts
+++ b/src/testing-utils.ts
@@ -14,7 +14,6 @@ import * as sinon from "sinon";

 import { ActionState, StateFeature } from "./action-common";
 import { ActionsEnv, getActionVersion } from "./actions-util";
-import * as actionsUtil from "./actions-util";
 import { AnalysisKind } from "./analyses";
 import * as apiClient from "./api-client";
 import { GitHubApiDetails } from "./api-client";
@@ -53,23 +52,6 @@ export const SAMPLE_DOTCOM_API_DETAILS = {
  apiURL: "https://api.github.com",
 };

-export function mockApiDetails(
-  apiDetails: Required<GitHubApiDetails>,
-  env: Env = getEnv(),
-) {
-  // This is a workaround to mock `api.getApiDetails()` since it doesn't seem to be possible to
-  // mock this directly. The difficulty is that `getApiDetails()` is called locally in
-  // `api-client.ts`, but `sinon.stub(api, "getApiDetails")` only affects calls to
-  // `getApiDetails()` via an imported `api` module.
-  const getRequiredInput = sinon.stub(actionsUtil, "getRequiredInput");
-  getRequiredInput.withArgs("token").returns(apiDetails.auth);
-
-  env.set("GITHUB_SERVER_URL", apiDetails.url);
-  env.set("GITHUB_API_URL", apiDetails.apiURL ?? "");
-
-  return getRequiredInput;
-}
-
 export const LINKED_CLI_VERSION = {
  cliVersion: defaults.cliVersion,
  tagName: defaults.bundleVersion,
--- a/src/tools-download.test.ts
+++ b/src/tools-download.test.ts
@@ -10,6 +10,7 @@ import { https } from "follow-redirects";
 import nock from "nock";
 import * as sinon from "sinon";

+import * as errors from "./errors";
 import { getRunnerLogger } from "./logging";
 import * as tar from "./tar";
 import { setupTests } from "./testing-utils";
@@ -164,7 +165,7 @@ test.serial(
 test.serial(
  "downloadAndExtract handles an unknown status as a non-HTTP error",
  async (t) => {
-    const asHTTPError = sinon.spy(util, "asHTTPError");
+    const asHTTPError = sinon.spy(errors, "asHTTPError");
    await util.withTmpDir(async (tmpDir) => {
      sinon.stub(process, "platform").value("linux");
      const archivePath = path.join(tmpDir, "codeql-bundle.tar.zst");
--- a/src/upload-lib.test.ts
+++ b/src/upload-lib.test.ts
@@ -10,17 +10,18 @@ import * as analyses from "./analyses";
 import { AnalysisKind, CodeQuality, CodeScanning } from "./analyses";
 import * as api from "./api-client";
 import * as diffUtils from "./diff-informed-analysis-utils";
+import { getEnv } from "./environment";
 import { getRunnerLogger, Logger } from "./logging";
 import * as sarif from "./sarif";
 import { setupTests } from "./testing-utils";
 import * as uploadLib from "./upload-lib";
 import { UploadPayload } from "./upload-lib/types";
-import { GitHubVariant, initializeEnvironment, withTmpDir } from "./util";
+import { GitHubVariant, withTmpDir } from "./util";

 setupTests(test);

 test.beforeEach(() => {
-  initializeEnvironment("1.2.3");
+  getEnv().initialise("1.2.3");
 });

 test.serial("validateSarifFileSchema - valid", (t) => {
--- a/src/upload-sarif-action.ts
+++ b/src/upload-sarif-action.ts
@@ -23,7 +23,6 @@ import {
  ConfigurationError,
  checkActionVersion,
  checkDiskUsage,
-  initializeEnvironment,
  shouldSkipSarifUpload,
  wrapError,
 } from "./util";
@@ -54,11 +53,13 @@ async function sendSuccessStatusReport(
  }
 }

-async function run({ startedAt, logger }: ActionState<["Base", "Logger"]>) {
+async function run(action: ActionState<["Base", "Env", "Logger"]>) {
  // To capture errors appropriately, keep as much code within the try-catch as
  // possible, and only use safe functions outside.
+  const logger = action.logger;
+
  try {
-    initializeEnvironment(getActionVersion());
+    action.env.initialise(getActionVersion());

    const gitHubVersion = await getGitHubVersion();
    checkActionVersion(getActionVersion(), gitHubVersion);
@@ -77,7 +78,7 @@ async function run({ startedAt, logger }: ActionState<["Base", "Logger"]>) {
    const startingStatusReportBase = await createStatusReportBase(
      ActionName.UploadSarif,
      "starting",
-      startedAt,
+      action.startedAt,
      undefined,
      await checkDiskUsage(logger),
      logger,
@@ -131,7 +132,7 @@ async function run({ startedAt, logger }: ActionState<["Base", "Logger"]>) {
      // so we can't wait for that here.
    }
    await sendSuccessStatusReport(
-      startedAt,
+      action.startedAt,
      codeScanningResult?.statusReport || {},
      logger,
    );
@@ -147,7 +148,7 @@ async function run({ startedAt, logger }: ActionState<["Base", "Logger"]>) {
    const errorStatusReportBase = await createStatusReportBase(
      ActionName.UploadSarif,
      getActionsStatus(error),
-      startedAt,
+      action.startedAt,
      undefined,
      await checkDiskUsage(logger),
      logger,
--- a/src/util.ts
+++ b/src/util.ts
@@ -20,20 +20,21 @@ import {
  getRequiredEnvParam,
  isInTestMode,
  exportEnvVar,
-  getEnv,
-  type Env,
 } from "./environment";
-import * as json from "./json";
-import { Language } from "./languages";
-import { Logger } from "./logging";
+import { ConfigurationError, getErrorMessage, wrapError } from "./errors";
+import { GitHubVariant, type GitHubVersion } from "./github";
+import type { Language } from "./languages";
+import type { Logger } from "./logging";

 // Re-export for backwards compatibility to avoid updating a lot of imports elsewhere.
+export * from "./errors";
 export {
  getRequiredEnvParam,
  getOptionalEnvVar,
  getEnv,
  isInTestMode,
 } from "./environment";
+export { GitHubVariant, type GitHubVersion } from "./github";

 /**
 * The name of the file containing the base database OIDs, as stored in the
@@ -47,9 +48,6 @@ const BASE_DATABASE_OIDS_FILE_NAME = "base-database-oids.json";
 */
 const BROKEN_VERSIONS = ["0.0.0-20211207"];

-/** A string representing a GitHub instance. */
-export type InstanceURL = string;
-
 /**
 * Default name of the debugging artifact.
 */
@@ -470,20 +468,6 @@ const CODEQL_ACTION_WARNED_ABOUT_VERSION_ENV_VAR =

 let hasBeenWarnedAboutVersion = false;

-export enum GitHubVariant {
-  /** [GitHub.com](https://github.com) */
-  DOTCOM = "GitHub.com",
-  /** [GitHub Enterprise Server](https://docs.github.com/en/enterprise-server@latest/admin/overview/about-github-enterprise-server) */
-  GHES = "GitHub Enterprise Server",
-  /** [GitHub Enterprise Cloud with data residency](https://docs.github.com/en/enterprise-cloud@latest/admin/data-residency/about-github-enterprise-cloud-with-data-residency) */
-  GHEC_DR = "GitHub Enterprise Cloud with data residency",
-}
-
-export type GitHubVersion =
-  | { type: GitHubVariant.DOTCOM }
-  | { type: GitHubVariant.GHEC_DR }
-  | { type: GitHubVariant.GHES; version: string };
-
 export function checkGitHubVersionInRange(
  version: GitHubVersion,
  logger: Logger,
@@ -552,54 +536,6 @@ export function assertNever(value: never): never {
  throw new ExhaustivityCheckingError(value);
 }

-/**
- * Set some initial environment variables that we can set even without
- * knowing what version of CodeQL we're running.
- */
-export function initializeEnvironment(version: string, env: Env = getEnv()) {
-  env.export(EnvVar.FEATURE_MULTI_LANGUAGE, "false");
-  env.export(EnvVar.FEATURE_SANDWICH, "false");
-  env.export(EnvVar.FEATURE_SARIF_COMBINE, "true");
-  env.export(EnvVar.FEATURE_WILL_UPLOAD, "true");
-  env.export(EnvVar.VERSION, version);
-}
-
-export class HTTPError extends Error {
-  public status: number;
-
-  constructor(message: string, status: number) {
-    super(message);
-    this.status = status;
-  }
-}
-
-/**
- * An Error class that indicates an error that occurred due to
- * a misconfiguration of the action or the CodeQL CLI.
- */
-export class ConfigurationError extends Error {}
-
-export function asHTTPError(arg: any): HTTPError | undefined {
-  if (!json.isObject<any>(arg) || !json.isString(arg.message)) {
-    return undefined;
-  }
-  if (Number.isInteger(arg.status)) {
-    return new HTTPError(arg.message, arg.status as number);
-  }
-  // See https://github.com/actions/toolkit/blob/acb230b99a46ed33a3f04a758cd68b47b9a82908/packages/tool-cache/src/tool-cache.ts#L19
-  if (Number.isInteger(arg.httpStatusCode)) {
-    return new HTTPError(arg.message, arg.httpStatusCode as number);
-  }
-  return undefined;
-}
-
-export async function codeQlVersionAtLeast(
-  codeql: CodeQL,
-  requiredVersion: string,
-): Promise<boolean> {
-  return semver.gte((await codeql.getVersion()).version, requiredVersion);
-}
-
 export function getBaseDatabaseOidsFilePath(
  config: ActionConfig<"dbLocation">,
 ): string {
@@ -867,20 +803,6 @@ export function parseMatrixInput(
  }
 }

-export function wrapError(error: unknown): Error {
-  return error instanceof Error ? error : new Error(String(error));
-}
-
-/**
- * Returns an appropriate message for the error.
- *
- * If the error is an `Error` instance, this returns the error message without
- * an `Error: ` prefix.
- */
-export function getErrorMessage(error: unknown): string {
-  return error instanceof Error ? error.message : String(error);
-}
-
 export function prettyPrintPack(pack: Pack) {
  return `${pack.name}${pack.version ? `@${pack.version}` : ""}${
    pack.path ? `:${pack.path}` : ""
--- a/unreleased-change-notes/README.md
+++ b/unreleased-change-notes/README.md
@@ -2,6 +2,16 @@

 Change-notes are Markdown files used to document user-facing changes. When making a change that affects users, create a Markdown file here that describes the change. During the next release, the change-note files in `unreleased-change-notes/` will automatically be added to `CHANGELOG.md`.

+### What do document
+
+Some guidelines to help you decide whether a change needs a change note:
+
+- New functionality that is gated behind a feature flag should be documented when it is added, highlighting that the feature will only be rolled out later. Ideally, this should also include an estimate for when the feature is expected to become available.
+- When a feature flag is removed and the gated functionality becomes the default behaviour, this does not need to be documented.
+- Changes that may require users to make changes to their workflows must be documented.
+
+If in doubt, see `CHANGELOG.md` for what we have included previously.
+
 ### Change-note file format

 Change-note files must follow a certain format so that they can be automatically validated and processed. Failure to follow the format will result in a failed PR check.
Author	SHA1	Message	Date
Michael B. Gale	c252c71195	Move `initializeEnvironment` out of `util.ts`	2026-10-16 22:15:06 +01:00
Michael B. Gale	a234b846e2	Remove unused type parameters from `Env` classes	2026-10-16 22:04:24 +01:00
Michael B. Gale	dc2ed81cc7	Remove `InstanceURL` from `util.ts`	2026-10-16 22:04:05 +01:00
Michael B. Gale	02283e9542	Move more GitHub-related definitions from `util.ts` to `github.ts`	2026-10-16 21:54:02 +01:00
Michael B. Gale	86bc4448d3	Mark additional imports in `util.ts` as `type`-only	2026-10-16 21:52:19 +01:00
Michael B. Gale	9c72af5b2b	Move `codeQlVersionAtLeast` out of `util.ts` and into `CodeQL`	2026-10-16 21:50:31 +01:00
Michael B. Gale	929f5c0db4	Move `isDiskConfigurationError` out of `codeql.ts`	2026-10-16 21:50:09 +01:00
Michael B. Gale	a76419a632	Move `wrapError` and `getErrorMessage` out of `util.ts`	2026-10-16 21:46:16 +01:00
Michael B. Gale	071544a67a	Move `HTTPError` out of `util.ts`	2026-10-16 21:40:48 +01:00
Michael B. Gale	8bdea824e2	Move `ConfigurationError` out of `util.ts`	2026-10-16 21:39:54 +01:00
Michael B. Gale	83e1837c6d	Merge pull request #4247 from github/mbg/copilot/clarify-feature-flags Add Copilot instructions for FFs, and update documentation more generally	2026-10-16 15:20:34 +00:00
Michael B. Gale	5ecf3b32e9	Suggest "Minor" prefix	2026-10-16 16:03:32 +01:00
Michael B. Gale	e461913b38	Drop "requests" again	2026-10-16 16:03:00 +01:00
Michael B. Gale	6992155901	Elaborate GHES details	2026-10-16 16:02:01 +01:00
Michael B. Gale	f3c93e3106	Add some guidelines for change notes	2026-10-16 15:32:50 +01:00
Michael B. Gale	2441e6e56e	Update "Review instructions" based on recent reviews	2026-10-16 15:31:56 +01:00
Michael B. Gale	0d2baf6822	Update `copilot-instructions.md` to mention feature flags	2026-10-16 15:11:17 +01:00
Henry Mercer	ae098fa9fe	Merge pull request #4242 from github/henrymercer/graduate-toolcache-cleanup Enable cleaning up toolcache bundles by default	2026-10-16 12:43:00 +00:00
Henry Mercer	4ebc48bf25	Remove the toolcache cleanup test override Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 9bf883d4-ecd7-4428-970f-86895f760571	2026-10-15 14:54:30 +01:00
Henry Mercer	1ec6b03cf4	Enable toolcache bundle cleanup by default Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 9bf883d4-ecd7-4428-970f-86895f760571	2026-10-15 14:54:30 +01:00