feat: adopt @actions/cache 6.2.0 (cache-mode skip + read-denied warning)

Bumps @actions/cache to ^6.2.0 and rebuilds the vendored dist bundles.
Note: package-lock.json must be regenerated with a registry install once
@actions/cache 6.2.0 is published to npm, before this is merged.

dist/restore-only/index.js

@@ -39021,7 +39021,7 @@ module.exports = { version: packageJson.version }
 /***/ 4012:
 /***/ ((module) => {
 
-module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.1.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
+module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.2.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
 
 /***/ })
 
@@ -43247,6 +43247,10 @@ const SystemTarPathOnWindows = `${process.env['SYSTEMDRIVE']}\\Windows\\System32
 const TarFilename = 'cache.tar';
 const constants_ManifestFilename = 'manifest.txt';
 const CacheFileSizeLimit = 10 * Math.pow(1024, 3); // 10GiB per repository
+// Prefix the cache backend embeds in a read-denial message (v2 twirp
+// GetCacheEntryDownloadURL error or the GHES v1 `_apis/artifactcache` 403 body).
+// Shared so cache.ts and cacheHttpClient.ts match the same contract value.
+const CacheReadDeniedMessagePrefix = 'cache read denied:';
 //# sourceMappingURL=constants.js.map
 ;// CONCATENATED MODULE: ./node_modules/@actions/cache/lib/internal/cacheUtils.js
 var cacheUtils_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _arguments, P, generator) {
@@ -92912,6 +92916,24 @@ function config_getCacheServiceVersion() {
         return 'v1';
     return process.env['ACTIONS_CACHE_SERVICE_V2'] ? 'v2' : 'v1';
 }
+// The cache-mode lattice: readable = {read, write}, writable = {write,
+// write-only}, none = neither.
+const KNOWN_CACHE_MODES = ['none', 'read', 'write', 'write-only'];
+// The effective cache-mode exported by the runner, or '' when not set.
+function config_getCacheMode() {
+    return (process.env['ACTIONS_CACHE_MODE'] || '').trim().toLowerCase();
+}
+// Unset or unrecognized modes are permissive so behavior matches today.
+function isCacheReadable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'read' || mode === 'write';
+}
+function config_isCacheWritable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'write' || mode === 'write-only';
+}
 function getCacheServiceURL() {
     const version = config_getCacheServiceVersion();
     // Based on the version of the cache service, we will determine which
@@ -92961,6 +92983,7 @@ var cacheHttpClient_awaiter = (undefined && undefined.__awaiter) || function (th
 
 
 
+
 function getCacheApiUrl(resource) {
     const baseUrl = getCacheServiceURL();
     if (!baseUrl) {
@@ -92988,6 +93011,7 @@ function createHttpClient() {
 }
 function getCacheEntry(keys, paths, options) {
     return cacheHttpClient_awaiter(this, void 0, void 0, function* () {
+        var _a;
         const httpClient = createHttpClient();
         const version = getCacheVersion(paths, options === null || options === void 0 ? void 0 : options.compressionMethod, options === null || options === void 0 ? void 0 : options.enableCrossOsArchive);
         const resource = `cache?keys=${encodeURIComponent(keys.join(','))}&version=${version}`;
@@ -93001,6 +93025,12 @@ function getCacheEntry(keys, paths, options) {
             return null;
         }
         if (!requestUtils_isSuccessStatusCode(response.statusCode)) {
+            // Only surface the receiver's body for a `cache read denied:` policy denial
+            // so callers can dispatch on it; keep the generic message otherwise.
+            const errorMessage = (_a = response.error) === null || _a === void 0 ? void 0 : _a.message;
+            if (errorMessage === null || errorMessage === void 0 ? void 0 : errorMessage.includes(CacheReadDeniedMessagePrefix)) {
+                throw new Error(errorMessage);
+            }
             throw new Error(`Cache service responded with ${response.statusCode}`);
         }
         const cacheResult = response.result;
@@ -94262,6 +94292,7 @@ var cache_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _ar
 
 
 
+
 class ValidationError extends Error {
     constructor(message) {
         super(message);
@@ -94277,19 +94308,20 @@ class ReserveCacheError extends Error {
     }
 }
 /**
- * Stable prefix the receiver writes into the cache reservation response when
+ * Stable prefix the cache service writes into the cache reservation response
- * the issuer downgraded the cache token to read-only (for example, because
+ * when the issuer downgraded the cache token to read-only (for example, because
  * the run was triggered by an untrusted event). saveCacheV1 / saveCacheV2
- * dispatch on this prefix to re-classify the failure as a
+ * dispatch on this prefix to re-classify the failure as a CacheWriteDeniedError
- * CacheWriteDeniedError so consumers (and the outer catch arm) can
+ * so consumers and tests can distinguish a policy denial from other reservation
- * distinguish a policy denial from other reservation failures.
+ * failures. Internally it is logged as a non-fatal warning like other
+ * best-effort save failures.
  */
 const CACHE_WRITE_DENIED_PREFIX = 'cache write denied:';
 /**
  * Raised when the cache backend refuses to reserve a writable cache entry
  * because the JWT issued for this run was scoped read-only (for example, the
  * run was triggered by an event the repository administrator classified as
- * untrusted). The receiver-supplied detail message always begins with
+ * untrusted). The service-supplied detail message always begins with
  * `cache write denied:` (the full error message includes additional context
  * like the cache key).
  *
@@ -94305,6 +94337,19 @@ class CacheWriteDeniedError extends ReserveCacheError {
         Object.setPrototypeOf(this, CacheWriteDeniedError.prototype);
     }
 }
+// Re-exported from constants so consumers keep referencing it here; the shared
+// value also drives detection in cacheHttpClient without duplicating the string.
+const CACHE_READ_DENIED_PREFIX = CacheReadDeniedMessagePrefix;
+// Raised when the cache backend denies a download URL because the run's token
+// has no readable cache scopes. Caching is best-effort, so restoreCache logs a
+// warning and reports a cache miss rather than rethrowing this.
+class CacheReadDeniedError extends Error {
+    constructor(message) {
+        super(message);
+        this.name = 'CacheReadDeniedError';
+        Object.setPrototypeOf(this, CacheReadDeniedError.prototype);
+    }
+}
 class FinalizeCacheError extends Error {
     constructor(message) {
         super(message);
@@ -94359,6 +94404,12 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         const cacheServiceVersion = config_getCacheServiceVersion();
         core_debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
+        const cacheMode = config_getCacheMode();
+        if (!isCacheReadable(cacheMode)) {
+            info(`Cache restore skipped: the effective cache-mode '${cacheMode}' does not permit reads.`);
+            core_debug(`Skipped restore for paths [${paths.join(', ')}] with primary key '${primaryKey}'.`);
+            return undefined;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield restoreCacheV2(paths, primaryKey, restoreKeys, options, enableCrossOsArchive);
@@ -94380,6 +94431,7 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         restoreKeys = restoreKeys || [];
         const keys = [primaryKey, ...restoreKeys];
         core_debug('Resolved Keys:');
@@ -94394,10 +94446,26 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         let archivePath = '';
         try {
             // path are needed to compute version
-            const cacheEntry = yield getCacheEntry(keys, paths, {
+            let cacheEntry;
-                compressionMethod,
+            try {
-                enableCrossOsArchive
+                cacheEntry = yield getCacheEntry(keys, paths, {
-            });
+                    compressionMethod,
+                    enableCrossOsArchive
+                });
+            }
+            catch (error) {
+                // The v1 artifact cache service returns HTTP 403 with a
+                // `cache read denied:` body when the run's token has no readable cache
+                // scopes. getCacheEntry lives in a dependency-free internal module and
+                // cannot import CacheReadDeniedError without a circular dependency, so it
+                // only surfaces the raw denial message; we classify it into the typed
+                // error here so the outer catch and consumers can dispatch on it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!(cacheEntry === null || cacheEntry === void 0 ? void 0 : cacheEntry.archiveLocation)) {
                 // Cache not found
                 return undefined;
@@ -94426,7 +94494,9 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
             }
             else {
                 // warn on cache restore failure and continue build
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94461,6 +94531,7 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         // Override UploadOptions to force the use of Azure
         options = Object.assign(Object.assign({}, options), { useAzureSdk: true });
         restoreKeys = restoreKeys || [];
@@ -94482,7 +94553,20 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 restoreKeys,
                 version: getCacheVersion(paths, compressionMethod, enableCrossOsArchive)
             };
-            const response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            let response;
+            try {
+                response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            }
+            catch (error) {
+                // The receiver returns twirp PermissionDenied (403) when the run's token
+                // has no readable cache scopes. The client wraps that 403, so the stable
+                // prefix is embedded in the message rather than leading it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!response.ok) {
                 core_debug(`Cache not found for version ${request.version} of keys: ${keys.join(', ')}`);
                 return undefined;
@@ -94517,8 +94601,10 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 throw error;
             }
             else {
-                // Supress all non-validation cache related errors because caching should be optional
+                // Suppress all non-validation cache related errors because caching should be optional
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94557,6 +94643,12 @@ function cache_saveCache(paths_1, key_1, options_1) {
         core.debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
         checkKey(key);
+        const cacheMode = getCacheMode();
+        if (!isCacheWritable(cacheMode)) {
+            core.info(`Cache save skipped: the effective cache-mode '${cacheMode}' does not permit writes.`);
+            core.debug(`Skipped save for paths [${paths.join(', ')}] with key '${key}'.`);
+            return -1;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield saveCacheV2(paths, key, options, enableCrossOsArchive);
@@ -94634,17 +94726,14 @@ function saveCacheV1(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                core.warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 core.info(`Failed to save: ${typedError.message}`);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94755,12 +94844,6 @@ function saveCacheV2(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                core.warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 core.info(`Failed to save: ${typedError.message}`);
             }
@@ -94768,7 +94851,10 @@ function saveCacheV2(paths_1, key_1, options_1) {
                 core.warning(typedError.message);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {

dist/restore/index.js

@@ -39021,7 +39021,7 @@ module.exports = { version: packageJson.version }
 /***/ 4012:
 /***/ ((module) => {
 
-module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.1.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
+module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.2.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
 
 /***/ })
 
@@ -43247,6 +43247,10 @@ const SystemTarPathOnWindows = `${process.env['SYSTEMDRIVE']}\\Windows\\System32
 const TarFilename = 'cache.tar';
 const constants_ManifestFilename = 'manifest.txt';
 const CacheFileSizeLimit = 10 * Math.pow(1024, 3); // 10GiB per repository
+// Prefix the cache backend embeds in a read-denial message (v2 twirp
+// GetCacheEntryDownloadURL error or the GHES v1 `_apis/artifactcache` 403 body).
+// Shared so cache.ts and cacheHttpClient.ts match the same contract value.
+const CacheReadDeniedMessagePrefix = 'cache read denied:';
 //# sourceMappingURL=constants.js.map
 ;// CONCATENATED MODULE: ./node_modules/@actions/cache/lib/internal/cacheUtils.js
 var cacheUtils_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _arguments, P, generator) {
@@ -92912,6 +92916,24 @@ function config_getCacheServiceVersion() {
         return 'v1';
     return process.env['ACTIONS_CACHE_SERVICE_V2'] ? 'v2' : 'v1';
 }
+// The cache-mode lattice: readable = {read, write}, writable = {write,
+// write-only}, none = neither.
+const KNOWN_CACHE_MODES = ['none', 'read', 'write', 'write-only'];
+// The effective cache-mode exported by the runner, or '' when not set.
+function config_getCacheMode() {
+    return (process.env['ACTIONS_CACHE_MODE'] || '').trim().toLowerCase();
+}
+// Unset or unrecognized modes are permissive so behavior matches today.
+function isCacheReadable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'read' || mode === 'write';
+}
+function config_isCacheWritable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'write' || mode === 'write-only';
+}
 function getCacheServiceURL() {
     const version = config_getCacheServiceVersion();
     // Based on the version of the cache service, we will determine which
@@ -92961,6 +92983,7 @@ var cacheHttpClient_awaiter = (undefined && undefined.__awaiter) || function (th
 
 
 
+
 function getCacheApiUrl(resource) {
     const baseUrl = getCacheServiceURL();
     if (!baseUrl) {
@@ -92988,6 +93011,7 @@ function createHttpClient() {
 }
 function getCacheEntry(keys, paths, options) {
     return cacheHttpClient_awaiter(this, void 0, void 0, function* () {
+        var _a;
         const httpClient = createHttpClient();
         const version = getCacheVersion(paths, options === null || options === void 0 ? void 0 : options.compressionMethod, options === null || options === void 0 ? void 0 : options.enableCrossOsArchive);
         const resource = `cache?keys=${encodeURIComponent(keys.join(','))}&version=${version}`;
@@ -93001,6 +93025,12 @@ function getCacheEntry(keys, paths, options) {
             return null;
         }
         if (!requestUtils_isSuccessStatusCode(response.statusCode)) {
+            // Only surface the receiver's body for a `cache read denied:` policy denial
+            // so callers can dispatch on it; keep the generic message otherwise.
+            const errorMessage = (_a = response.error) === null || _a === void 0 ? void 0 : _a.message;
+            if (errorMessage === null || errorMessage === void 0 ? void 0 : errorMessage.includes(CacheReadDeniedMessagePrefix)) {
+                throw new Error(errorMessage);
+            }
             throw new Error(`Cache service responded with ${response.statusCode}`);
         }
         const cacheResult = response.result;
@@ -94262,6 +94292,7 @@ var cache_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _ar
 
 
 
+
 class ValidationError extends Error {
     constructor(message) {
         super(message);
@@ -94277,19 +94308,20 @@ class ReserveCacheError extends Error {
     }
 }
 /**
- * Stable prefix the receiver writes into the cache reservation response when
+ * Stable prefix the cache service writes into the cache reservation response
- * the issuer downgraded the cache token to read-only (for example, because
+ * when the issuer downgraded the cache token to read-only (for example, because
  * the run was triggered by an untrusted event). saveCacheV1 / saveCacheV2
- * dispatch on this prefix to re-classify the failure as a
+ * dispatch on this prefix to re-classify the failure as a CacheWriteDeniedError
- * CacheWriteDeniedError so consumers (and the outer catch arm) can
+ * so consumers and tests can distinguish a policy denial from other reservation
- * distinguish a policy denial from other reservation failures.
+ * failures. Internally it is logged as a non-fatal warning like other
+ * best-effort save failures.
  */
 const CACHE_WRITE_DENIED_PREFIX = 'cache write denied:';
 /**
  * Raised when the cache backend refuses to reserve a writable cache entry
  * because the JWT issued for this run was scoped read-only (for example, the
  * run was triggered by an event the repository administrator classified as
- * untrusted). The receiver-supplied detail message always begins with
+ * untrusted). The service-supplied detail message always begins with
  * `cache write denied:` (the full error message includes additional context
  * like the cache key).
  *
@@ -94305,6 +94337,19 @@ class CacheWriteDeniedError extends ReserveCacheError {
         Object.setPrototypeOf(this, CacheWriteDeniedError.prototype);
     }
 }
+// Re-exported from constants so consumers keep referencing it here; the shared
+// value also drives detection in cacheHttpClient without duplicating the string.
+const CACHE_READ_DENIED_PREFIX = CacheReadDeniedMessagePrefix;
+// Raised when the cache backend denies a download URL because the run's token
+// has no readable cache scopes. Caching is best-effort, so restoreCache logs a
+// warning and reports a cache miss rather than rethrowing this.
+class CacheReadDeniedError extends Error {
+    constructor(message) {
+        super(message);
+        this.name = 'CacheReadDeniedError';
+        Object.setPrototypeOf(this, CacheReadDeniedError.prototype);
+    }
+}
 class FinalizeCacheError extends Error {
     constructor(message) {
         super(message);
@@ -94359,6 +94404,12 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         const cacheServiceVersion = config_getCacheServiceVersion();
         core_debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
+        const cacheMode = config_getCacheMode();
+        if (!isCacheReadable(cacheMode)) {
+            info(`Cache restore skipped: the effective cache-mode '${cacheMode}' does not permit reads.`);
+            core_debug(`Skipped restore for paths [${paths.join(', ')}] with primary key '${primaryKey}'.`);
+            return undefined;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield restoreCacheV2(paths, primaryKey, restoreKeys, options, enableCrossOsArchive);
@@ -94380,6 +94431,7 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         restoreKeys = restoreKeys || [];
         const keys = [primaryKey, ...restoreKeys];
         core_debug('Resolved Keys:');
@@ -94394,10 +94446,26 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         let archivePath = '';
         try {
             // path are needed to compute version
-            const cacheEntry = yield getCacheEntry(keys, paths, {
+            let cacheEntry;
-                compressionMethod,
+            try {
-                enableCrossOsArchive
+                cacheEntry = yield getCacheEntry(keys, paths, {
-            });
+                    compressionMethod,
+                    enableCrossOsArchive
+                });
+            }
+            catch (error) {
+                // The v1 artifact cache service returns HTTP 403 with a
+                // `cache read denied:` body when the run's token has no readable cache
+                // scopes. getCacheEntry lives in a dependency-free internal module and
+                // cannot import CacheReadDeniedError without a circular dependency, so it
+                // only surfaces the raw denial message; we classify it into the typed
+                // error here so the outer catch and consumers can dispatch on it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!(cacheEntry === null || cacheEntry === void 0 ? void 0 : cacheEntry.archiveLocation)) {
                 // Cache not found
                 return undefined;
@@ -94426,7 +94494,9 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
             }
             else {
                 // warn on cache restore failure and continue build
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94461,6 +94531,7 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         // Override UploadOptions to force the use of Azure
         options = Object.assign(Object.assign({}, options), { useAzureSdk: true });
         restoreKeys = restoreKeys || [];
@@ -94482,7 +94553,20 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 restoreKeys,
                 version: getCacheVersion(paths, compressionMethod, enableCrossOsArchive)
             };
-            const response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            let response;
+            try {
+                response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            }
+            catch (error) {
+                // The receiver returns twirp PermissionDenied (403) when the run's token
+                // has no readable cache scopes. The client wraps that 403, so the stable
+                // prefix is embedded in the message rather than leading it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!response.ok) {
                 core_debug(`Cache not found for version ${request.version} of keys: ${keys.join(', ')}`);
                 return undefined;
@@ -94517,8 +94601,10 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 throw error;
             }
             else {
-                // Supress all non-validation cache related errors because caching should be optional
+                // Suppress all non-validation cache related errors because caching should be optional
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94557,6 +94643,12 @@ function cache_saveCache(paths_1, key_1, options_1) {
         core.debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
         checkKey(key);
+        const cacheMode = getCacheMode();
+        if (!isCacheWritable(cacheMode)) {
+            core.info(`Cache save skipped: the effective cache-mode '${cacheMode}' does not permit writes.`);
+            core.debug(`Skipped save for paths [${paths.join(', ')}] with key '${key}'.`);
+            return -1;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield saveCacheV2(paths, key, options, enableCrossOsArchive);
@@ -94634,17 +94726,14 @@ function saveCacheV1(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                core.warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 core.info(`Failed to save: ${typedError.message}`);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94755,12 +94844,6 @@ function saveCacheV2(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                core.warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 core.info(`Failed to save: ${typedError.message}`);
             }
@@ -94768,7 +94851,10 @@ function saveCacheV2(paths_1, key_1, options_1) {
                 core.warning(typedError.message);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {

dist/save-only/index.js

@@ -39021,7 +39021,7 @@ module.exports = { version: packageJson.version }
 /***/ 4012:
 /***/ ((module) => {
 
-module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.1.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
+module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.2.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
 
 /***/ })
 
@@ -43254,6 +43254,10 @@ const SystemTarPathOnWindows = `${process.env['SYSTEMDRIVE']}\\Windows\\System32
 const TarFilename = 'cache.tar';
 const ManifestFilename = 'manifest.txt';
 const CacheFileSizeLimit = 10 * Math.pow(1024, 3); // 10GiB per repository
+// Prefix the cache backend embeds in a read-denial message (v2 twirp
+// GetCacheEntryDownloadURL error or the GHES v1 `_apis/artifactcache` 403 body).
+// Shared so cache.ts and cacheHttpClient.ts match the same contract value.
+const constants_CacheReadDeniedMessagePrefix = 'cache read denied:';
 //# sourceMappingURL=constants.js.map
 ;// CONCATENATED MODULE: ./node_modules/@actions/cache/lib/internal/cacheUtils.js
 var cacheUtils_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _arguments, P, generator) {
@@ -92918,6 +92922,24 @@ function config_getCacheServiceVersion() {
         return 'v1';
     return process.env['ACTIONS_CACHE_SERVICE_V2'] ? 'v2' : 'v1';
 }
+// The cache-mode lattice: readable = {read, write}, writable = {write,
+// write-only}, none = neither.
+const KNOWN_CACHE_MODES = ['none', 'read', 'write', 'write-only'];
+// The effective cache-mode exported by the runner, or '' when not set.
+function config_getCacheMode() {
+    return (process.env['ACTIONS_CACHE_MODE'] || '').trim().toLowerCase();
+}
+// Unset or unrecognized modes are permissive so behavior matches today.
+function config_isCacheReadable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'read' || mode === 'write';
+}
+function isCacheWritable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'write' || mode === 'write-only';
+}
 function getCacheServiceURL() {
     const version = config_getCacheServiceVersion();
     // Based on the version of the cache service, we will determine which
@@ -92967,6 +92989,7 @@ var cacheHttpClient_awaiter = (undefined && undefined.__awaiter) || function (th
 
 
 
+
 function getCacheApiUrl(resource) {
     const baseUrl = getCacheServiceURL();
     if (!baseUrl) {
@@ -92994,6 +93017,7 @@ function createHttpClient() {
 }
 function getCacheEntry(keys, paths, options) {
     return cacheHttpClient_awaiter(this, void 0, void 0, function* () {
+        var _a;
         const httpClient = createHttpClient();
         const version = utils.getCacheVersion(paths, options === null || options === void 0 ? void 0 : options.compressionMethod, options === null || options === void 0 ? void 0 : options.enableCrossOsArchive);
         const resource = `cache?keys=${encodeURIComponent(keys.join(','))}&version=${version}`;
@@ -93007,6 +93031,12 @@ function getCacheEntry(keys, paths, options) {
             return null;
         }
         if (!isSuccessStatusCode(response.statusCode)) {
+            // Only surface the receiver's body for a `cache read denied:` policy denial
+            // so callers can dispatch on it; keep the generic message otherwise.
+            const errorMessage = (_a = response.error) === null || _a === void 0 ? void 0 : _a.message;
+            if (errorMessage === null || errorMessage === void 0 ? void 0 : errorMessage.includes(CacheReadDeniedMessagePrefix)) {
+                throw new Error(errorMessage);
+            }
             throw new Error(`Cache service responded with ${response.statusCode}`);
         }
         const cacheResult = response.result;
@@ -94267,6 +94297,7 @@ var cache_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _ar
 
 
 
+
 class ValidationError extends Error {
     constructor(message) {
         super(message);
@@ -94282,19 +94313,20 @@ class ReserveCacheError extends Error {
     }
 }
 /**
- * Stable prefix the receiver writes into the cache reservation response when
+ * Stable prefix the cache service writes into the cache reservation response
- * the issuer downgraded the cache token to read-only (for example, because
+ * when the issuer downgraded the cache token to read-only (for example, because
  * the run was triggered by an untrusted event). saveCacheV1 / saveCacheV2
- * dispatch on this prefix to re-classify the failure as a
+ * dispatch on this prefix to re-classify the failure as a CacheWriteDeniedError
- * CacheWriteDeniedError so consumers (and the outer catch arm) can
+ * so consumers and tests can distinguish a policy denial from other reservation
- * distinguish a policy denial from other reservation failures.
+ * failures. Internally it is logged as a non-fatal warning like other
+ * best-effort save failures.
  */
 const CACHE_WRITE_DENIED_PREFIX = 'cache write denied:';
 /**
  * Raised when the cache backend refuses to reserve a writable cache entry
  * because the JWT issued for this run was scoped read-only (for example, the
  * run was triggered by an event the repository administrator classified as
- * untrusted). The receiver-supplied detail message always begins with
+ * untrusted). The service-supplied detail message always begins with
  * `cache write denied:` (the full error message includes additional context
  * like the cache key).
  *
@@ -94310,6 +94342,19 @@ class CacheWriteDeniedError extends ReserveCacheError {
         Object.setPrototypeOf(this, CacheWriteDeniedError.prototype);
     }
 }
+// Re-exported from constants so consumers keep referencing it here; the shared
+// value also drives detection in cacheHttpClient without duplicating the string.
+const CACHE_READ_DENIED_PREFIX = (/* unused pure expression or super */ null && (CacheReadDeniedMessagePrefix));
+// Raised when the cache backend denies a download URL because the run's token
+// has no readable cache scopes. Caching is best-effort, so restoreCache logs a
+// warning and reports a cache miss rather than rethrowing this.
+class CacheReadDeniedError extends Error {
+    constructor(message) {
+        super(message);
+        this.name = 'CacheReadDeniedError';
+        Object.setPrototypeOf(this, CacheReadDeniedError.prototype);
+    }
+}
 class FinalizeCacheError extends Error {
     constructor(message) {
         super(message);
@@ -94364,6 +94409,12 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         const cacheServiceVersion = getCacheServiceVersion();
         core.debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
+        const cacheMode = getCacheMode();
+        if (!isCacheReadable(cacheMode)) {
+            core.info(`Cache restore skipped: the effective cache-mode '${cacheMode}' does not permit reads.`);
+            core.debug(`Skipped restore for paths [${paths.join(', ')}] with primary key '${primaryKey}'.`);
+            return undefined;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield restoreCacheV2(paths, primaryKey, restoreKeys, options, enableCrossOsArchive);
@@ -94385,6 +94436,7 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         restoreKeys = restoreKeys || [];
         const keys = [primaryKey, ...restoreKeys];
         core.debug('Resolved Keys:');
@@ -94399,10 +94451,26 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         let archivePath = '';
         try {
             // path are needed to compute version
-            const cacheEntry = yield cacheHttpClient.getCacheEntry(keys, paths, {
+            let cacheEntry;
-                compressionMethod,
+            try {
-                enableCrossOsArchive
+                cacheEntry = yield cacheHttpClient.getCacheEntry(keys, paths, {
-            });
+                    compressionMethod,
+                    enableCrossOsArchive
+                });
+            }
+            catch (error) {
+                // The v1 artifact cache service returns HTTP 403 with a
+                // `cache read denied:` body when the run's token has no readable cache
+                // scopes. getCacheEntry lives in a dependency-free internal module and
+                // cannot import CacheReadDeniedError without a circular dependency, so it
+                // only surfaces the raw denial message; we classify it into the typed
+                // error here so the outer catch and consumers can dispatch on it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!(cacheEntry === null || cacheEntry === void 0 ? void 0 : cacheEntry.archiveLocation)) {
                 // Cache not found
                 return undefined;
@@ -94431,7 +94499,9 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
             }
             else {
                 // warn on cache restore failure and continue build
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94466,6 +94536,7 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         // Override UploadOptions to force the use of Azure
         options = Object.assign(Object.assign({}, options), { useAzureSdk: true });
         restoreKeys = restoreKeys || [];
@@ -94487,7 +94558,20 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 restoreKeys,
                 version: utils.getCacheVersion(paths, compressionMethod, enableCrossOsArchive)
             };
-            const response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            let response;
+            try {
+                response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            }
+            catch (error) {
+                // The receiver returns twirp PermissionDenied (403) when the run's token
+                // has no readable cache scopes. The client wraps that 403, so the stable
+                // prefix is embedded in the message rather than leading it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!response.ok) {
                 core.debug(`Cache not found for version ${request.version} of keys: ${keys.join(', ')}`);
                 return undefined;
@@ -94522,8 +94606,10 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 throw error;
             }
             else {
-                // Supress all non-validation cache related errors because caching should be optional
+                // Suppress all non-validation cache related errors because caching should be optional
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94562,6 +94648,12 @@ function cache_saveCache(paths_1, key_1, options_1) {
         core_debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
         checkKey(key);
+        const cacheMode = config_getCacheMode();
+        if (!isCacheWritable(cacheMode)) {
+            info(`Cache save skipped: the effective cache-mode '${cacheMode}' does not permit writes.`);
+            core_debug(`Skipped save for paths [${paths.join(', ')}] with key '${key}'.`);
+            return -1;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield saveCacheV2(paths, key, options, enableCrossOsArchive);
@@ -94639,17 +94731,14 @@ function saveCacheV1(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 info(`Failed to save: ${typedError.message}`);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94760,12 +94849,6 @@ function saveCacheV2(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 info(`Failed to save: ${typedError.message}`);
             }
@@ -94773,7 +94856,10 @@ function saveCacheV2(paths_1, key_1, options_1) {
                 warning(typedError.message);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {

dist/save/index.js

@@ -39021,7 +39021,7 @@ module.exports = { version: packageJson.version }
 /***/ 4012:
 /***/ ((module) => {
 
-module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.1.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
+module.exports = /*#__PURE__*/JSON.parse('{"name":"@actions/cache","version":"6.2.0","description":"Actions cache lib","keywords":["github","actions","cache"],"homepage":"https://github.com/actions/toolkit/tree/main/packages/cache","license":"MIT","type":"module","main":"lib/cache.js","types":"lib/cache.d.ts","exports":{".":{"types":"./lib/cache.d.ts","import":"./lib/cache.js"}},"directories":{"lib":"lib","test":"__tests__"},"files":["lib","!.DS_Store"],"publishConfig":{"access":"public"},"repository":{"type":"git","url":"git+https://github.com/actions/toolkit.git","directory":"packages/cache"},"scripts":{"audit-moderate":"npm install && npm audit --json --audit-level=moderate > audit.json","test":"echo \\"Error: run tests from root\\" && exit 1","tsc":"tsc && cp src/internal/shared/package-version.cjs lib/internal/shared/"},"bugs":{"url":"https://github.com/actions/toolkit/issues"},"dependencies":{"@actions/core":"^3.0.1","@actions/exec":"^3.0.0","@actions/glob":"^0.6.1","@actions/http-client":"^4.0.1","@actions/io":"^3.0.2","@azure/core-rest-pipeline":"^1.23.0","@azure/storage-blob":"^12.31.0","@protobuf-ts/runtime-rpc":"^2.11.1","semver":"^7.7.4"},"devDependencies":{"@protobuf-ts/plugin":"^2.11.1","@types/node":"^25.6.0","@types/semver":"^7.7.1","typescript":"^5.9.3"},"overrides":{"uri-js":"npm:uri-js-replace@^1.0.1","node-fetch":"^3.3.2"}}');
 
 /***/ })
 
@@ -43254,6 +43254,10 @@ const SystemTarPathOnWindows = `${process.env['SYSTEMDRIVE']}\\Windows\\System32
 const TarFilename = 'cache.tar';
 const ManifestFilename = 'manifest.txt';
 const CacheFileSizeLimit = 10 * Math.pow(1024, 3); // 10GiB per repository
+// Prefix the cache backend embeds in a read-denial message (v2 twirp
+// GetCacheEntryDownloadURL error or the GHES v1 `_apis/artifactcache` 403 body).
+// Shared so cache.ts and cacheHttpClient.ts match the same contract value.
+const constants_CacheReadDeniedMessagePrefix = 'cache read denied:';
 //# sourceMappingURL=constants.js.map
 ;// CONCATENATED MODULE: ./node_modules/@actions/cache/lib/internal/cacheUtils.js
 var cacheUtils_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _arguments, P, generator) {
@@ -92918,6 +92922,24 @@ function config_getCacheServiceVersion() {
         return 'v1';
     return process.env['ACTIONS_CACHE_SERVICE_V2'] ? 'v2' : 'v1';
 }
+// The cache-mode lattice: readable = {read, write}, writable = {write,
+// write-only}, none = neither.
+const KNOWN_CACHE_MODES = ['none', 'read', 'write', 'write-only'];
+// The effective cache-mode exported by the runner, or '' when not set.
+function config_getCacheMode() {
+    return (process.env['ACTIONS_CACHE_MODE'] || '').trim().toLowerCase();
+}
+// Unset or unrecognized modes are permissive so behavior matches today.
+function config_isCacheReadable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'read' || mode === 'write';
+}
+function isCacheWritable(mode) {
+    if (!KNOWN_CACHE_MODES.includes(mode))
+        return true;
+    return mode === 'write' || mode === 'write-only';
+}
 function getCacheServiceURL() {
     const version = config_getCacheServiceVersion();
     // Based on the version of the cache service, we will determine which
@@ -92967,6 +92989,7 @@ var cacheHttpClient_awaiter = (undefined && undefined.__awaiter) || function (th
 
 
 
+
 function getCacheApiUrl(resource) {
     const baseUrl = getCacheServiceURL();
     if (!baseUrl) {
@@ -92994,6 +93017,7 @@ function createHttpClient() {
 }
 function getCacheEntry(keys, paths, options) {
     return cacheHttpClient_awaiter(this, void 0, void 0, function* () {
+        var _a;
         const httpClient = createHttpClient();
         const version = utils.getCacheVersion(paths, options === null || options === void 0 ? void 0 : options.compressionMethod, options === null || options === void 0 ? void 0 : options.enableCrossOsArchive);
         const resource = `cache?keys=${encodeURIComponent(keys.join(','))}&version=${version}`;
@@ -93007,6 +93031,12 @@ function getCacheEntry(keys, paths, options) {
             return null;
         }
         if (!isSuccessStatusCode(response.statusCode)) {
+            // Only surface the receiver's body for a `cache read denied:` policy denial
+            // so callers can dispatch on it; keep the generic message otherwise.
+            const errorMessage = (_a = response.error) === null || _a === void 0 ? void 0 : _a.message;
+            if (errorMessage === null || errorMessage === void 0 ? void 0 : errorMessage.includes(CacheReadDeniedMessagePrefix)) {
+                throw new Error(errorMessage);
+            }
             throw new Error(`Cache service responded with ${response.statusCode}`);
         }
         const cacheResult = response.result;
@@ -94267,6 +94297,7 @@ var cache_awaiter = (undefined && undefined.__awaiter) || function (thisArg, _ar
 
 
 
+
 class ValidationError extends Error {
     constructor(message) {
         super(message);
@@ -94282,19 +94313,20 @@ class ReserveCacheError extends Error {
     }
 }
 /**
- * Stable prefix the receiver writes into the cache reservation response when
+ * Stable prefix the cache service writes into the cache reservation response
- * the issuer downgraded the cache token to read-only (for example, because
+ * when the issuer downgraded the cache token to read-only (for example, because
  * the run was triggered by an untrusted event). saveCacheV1 / saveCacheV2
- * dispatch on this prefix to re-classify the failure as a
+ * dispatch on this prefix to re-classify the failure as a CacheWriteDeniedError
- * CacheWriteDeniedError so consumers (and the outer catch arm) can
+ * so consumers and tests can distinguish a policy denial from other reservation
- * distinguish a policy denial from other reservation failures.
+ * failures. Internally it is logged as a non-fatal warning like other
+ * best-effort save failures.
  */
 const CACHE_WRITE_DENIED_PREFIX = 'cache write denied:';
 /**
  * Raised when the cache backend refuses to reserve a writable cache entry
  * because the JWT issued for this run was scoped read-only (for example, the
  * run was triggered by an event the repository administrator classified as
- * untrusted). The receiver-supplied detail message always begins with
+ * untrusted). The service-supplied detail message always begins with
  * `cache write denied:` (the full error message includes additional context
  * like the cache key).
  *
@@ -94310,6 +94342,19 @@ class CacheWriteDeniedError extends ReserveCacheError {
         Object.setPrototypeOf(this, CacheWriteDeniedError.prototype);
     }
 }
+// Re-exported from constants so consumers keep referencing it here; the shared
+// value also drives detection in cacheHttpClient without duplicating the string.
+const CACHE_READ_DENIED_PREFIX = (/* unused pure expression or super */ null && (CacheReadDeniedMessagePrefix));
+// Raised when the cache backend denies a download URL because the run's token
+// has no readable cache scopes. Caching is best-effort, so restoreCache logs a
+// warning and reports a cache miss rather than rethrowing this.
+class CacheReadDeniedError extends Error {
+    constructor(message) {
+        super(message);
+        this.name = 'CacheReadDeniedError';
+        Object.setPrototypeOf(this, CacheReadDeniedError.prototype);
+    }
+}
 class FinalizeCacheError extends Error {
     constructor(message) {
         super(message);
@@ -94364,6 +94409,12 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         const cacheServiceVersion = getCacheServiceVersion();
         core.debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
+        const cacheMode = getCacheMode();
+        if (!isCacheReadable(cacheMode)) {
+            core.info(`Cache restore skipped: the effective cache-mode '${cacheMode}' does not permit reads.`);
+            core.debug(`Skipped restore for paths [${paths.join(', ')}] with primary key '${primaryKey}'.`);
+            return undefined;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield restoreCacheV2(paths, primaryKey, restoreKeys, options, enableCrossOsArchive);
@@ -94385,6 +94436,7 @@ function restoreCache(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         restoreKeys = restoreKeys || [];
         const keys = [primaryKey, ...restoreKeys];
         core.debug('Resolved Keys:');
@@ -94399,10 +94451,26 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
         let archivePath = '';
         try {
             // path are needed to compute version
-            const cacheEntry = yield cacheHttpClient.getCacheEntry(keys, paths, {
+            let cacheEntry;
-                compressionMethod,
+            try {
-                enableCrossOsArchive
+                cacheEntry = yield cacheHttpClient.getCacheEntry(keys, paths, {
-            });
+                    compressionMethod,
+                    enableCrossOsArchive
+                });
+            }
+            catch (error) {
+                // The v1 artifact cache service returns HTTP 403 with a
+                // `cache read denied:` body when the run's token has no readable cache
+                // scopes. getCacheEntry lives in a dependency-free internal module and
+                // cannot import CacheReadDeniedError without a circular dependency, so it
+                // only surfaces the raw denial message; we classify it into the typed
+                // error here so the outer catch and consumers can dispatch on it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!(cacheEntry === null || cacheEntry === void 0 ? void 0 : cacheEntry.archiveLocation)) {
                 // Cache not found
                 return undefined;
@@ -94431,7 +94499,9 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
             }
             else {
                 // warn on cache restore failure and continue build
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94466,6 +94536,7 @@ function restoreCacheV1(paths_1, primaryKey_1, restoreKeys_1, options_1) {
  */
 function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
     return cache_awaiter(this, arguments, void 0, function* (paths, primaryKey, restoreKeys, options, enableCrossOsArchive = false) {
+        var _a;
         // Override UploadOptions to force the use of Azure
         options = Object.assign(Object.assign({}, options), { useAzureSdk: true });
         restoreKeys = restoreKeys || [];
@@ -94487,7 +94558,20 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 restoreKeys,
                 version: utils.getCacheVersion(paths, compressionMethod, enableCrossOsArchive)
             };
-            const response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            let response;
+            try {
+                response = yield twirpClient.GetCacheEntryDownloadURL(request);
+            }
+            catch (error) {
+                // The receiver returns twirp PermissionDenied (403) when the run's token
+                // has no readable cache scopes. The client wraps that 403, so the stable
+                // prefix is embedded in the message rather than leading it.
+                const errorMessage = (_a = error === null || error === void 0 ? void 0 : error.message) !== null && _a !== void 0 ? _a : '';
+                if (errorMessage.includes(CACHE_READ_DENIED_PREFIX)) {
+                    throw new CacheReadDeniedError(errorMessage);
+                }
+                throw error;
+            }
             if (!response.ok) {
                 core.debug(`Cache not found for version ${request.version} of keys: ${keys.join(', ')}`);
                 return undefined;
@@ -94522,8 +94606,10 @@ function restoreCacheV2(paths_1, primaryKey_1, restoreKeys_1, options_1) {
                 throw error;
             }
             else {
-                // Supress all non-validation cache related errors because caching should be optional
+                // Suppress all non-validation cache related errors because caching should be optional
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A read denied by policy (CacheReadDeniedError) is not an HttpClientError
+                // so it falls here and is warned, treated as a cache miss.
                 if (typedError instanceof HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94562,6 +94648,12 @@ function cache_saveCache(paths_1, key_1, options_1) {
         core_debug(`Cache service version: ${cacheServiceVersion}`);
         checkPaths(paths);
         checkKey(key);
+        const cacheMode = config_getCacheMode();
+        if (!isCacheWritable(cacheMode)) {
+            info(`Cache save skipped: the effective cache-mode '${cacheMode}' does not permit writes.`);
+            core_debug(`Skipped save for paths [${paths.join(', ')}] with key '${key}'.`);
+            return -1;
+        }
         switch (cacheServiceVersion) {
             case 'v2':
                 return yield saveCacheV2(paths, key, options, enableCrossOsArchive);
@@ -94639,17 +94731,14 @@ function saveCacheV1(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 info(`Failed to save: ${typedError.message}`);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {
@@ -94760,12 +94849,6 @@ function saveCacheV2(paths_1, key_1, options_1) {
             if (typedError.name === ValidationError.name) {
                 throw error;
             }
-            else if (typedError.name === CacheWriteDeniedError.name) {
-                // Cache write was denied by policy (read-only token). Surface to the
-                // customer at warning level so it is visible in the workflow log
-                // without failing the run.
-                warning(`Failed to save: ${typedError.message}`);
-            }
             else if (typedError.name === ReserveCacheError.name) {
                 info(`Failed to save: ${typedError.message}`);
             }
@@ -94773,7 +94856,10 @@ function saveCacheV2(paths_1, key_1, options_1) {
                 warning(typedError.message);
             }
             else {
-                // Log server errors (5xx) as errors, all other errors as warnings
+                // Log server errors (5xx) as errors, all other errors as warnings.
+                // A write denied by policy (CacheWriteDeniedError) is not an
+                // HttpClientError and its name does not match the ReserveCacheError arm,
+                // so it falls here and is warned without failing the run.
                 if (typedError instanceof lib_HttpClientError &&
                     typeof typedError.statusCode === 'number' &&
                     typedError.statusCode >= 500) {

package.json

@@ -24,7 +24,7 @@
   "author": "GitHub",
   "license": "MIT",
   "dependencies": {
-    "@actions/cache": "^6.1.0",
+    "@actions/cache": "^6.2.0",
     "@actions/core": "^3.0.1",
     "@actions/exec": "^3.0.0",
     "@actions/io": "^3.0.2"