{"record":{"id":"86dfcab82bba03fb","repo":"mastra-ai/mastra","slug":"worker-name-not-found-available-this-wor","errorCode":null,"errorMessage":"Worker \"${name}\" not found. Available: ${this.#workers.map(w => w.name).join(', ')}","messagePattern":"Worker \"(.+?)\" not found\\. Available: (.+?)","errorType":"exception","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"packages/core/src/mastra/index.ts","lineNumber":6106,"sourceCode":"        const { AgentScheduleWorker } = await import('../schedules/worker');\n        const asw = new AgentScheduleWorker();\n        asw.__registerMastra(this);\n        this.#workers.push(asw);\n      }\n    }\n\n    const deps: WorkerDeps = {\n      pubsub: this.#pubsub,\n      storage: this.#storage!,\n      logger: this.#logger as unknown as IMastraLogger,\n      mastra: this,\n    };\n\n    let targets: MastraWorker[];\n    if (name) {\n      targets = this.#workers.filter(w => w.name === name);\n      if (targets.length === 0) {\n        throw new Error(`Worker \"${name}\" not found. Available: ${this.#workers.map(w => w.name).join(', ')}`);\n      }\n    } else if (this.#workerFilter) {\n      targets = this.#workers.filter(w => this.#workerFilter!.has(w.name));\n      if (targets.length === 0) {\n        this.#logger?.warn?.(\n          `MASTRA_WORKERS=${[...this.#workerFilter].join(',')} did not match any registered workers (have: ${this.#workers.map(w => w.name).join(', ')})`,\n        );\n      }\n    } else {\n      targets = this.#workers;\n    }\n\n    // Rehydrate persisted workflow definitions (after storage.init() above).\n    if (this.#storage) {\n      await this.#loadDynamicWorkflows();\n    }\n\n    // When explicitly starting the backgroundTasks worker (e.g.","sourceCodeStart":6088,"sourceCodeEnd":6124,"githubUrl":"https://github.com/mastra-ai/mastra/blob/75dd419e613fe9c39f846ffc500716141b74fda6/packages/core/src/mastra/index.ts#L6088-L6124","documentation":"When starting/filtering workers, Mastra matches the requested name against registered MastraWorker instances. If no worker with that name is registered it throws a plain Error that helpfully lists the available worker names so the caller can self-correct.","triggerScenarios":"Calling the workers runner (e.g. startWorkers(name)) with a name that does not exactly equal any registered worker's name; the empty-string check means any truthy-but-unmatched name triggers this.","commonSituations":"Typo in the worker name; name case mismatch; the MASTRA_WORKERS env filter naming a worker that no longer exists; worker registered only in another Mastra instance/entrypoint.","solutions":["Read the 'Available:' list in the message and use one of those exact names.","Fix the name's spelling/casing to match the registration (strict equality on w.name).","Register the missing worker on this Mastra instance before starting it.","Update the MASTRA_WORKERS filter to reference currently registered worker names."],"exampleFix":"// before\nmastra.startWorkers('email-worker'); // registered as 'emailWorker'\n// after\nmastra.startWorkers('emailWorker');","handlingStrategy":"validation","validationCode":"const available = mastra.getWorkers?.().map(w => w.name) ?? [];\nif (name && !available.includes(name)) {\n  throw new Error(`Worker \"${name}\" not registered. Available: ${available.join(', ')}`);\n}","typeGuard":null,"tryCatchPattern":"try {\n  mastra.startWorkers(name);\n} catch (e) {\n  if (e instanceof Error && e.message.includes('not found. Available:')) {\n    console.warn(`Unknown worker \"${name}\"; starting all registered workers instead.`);\n    mastra.startWorkers();\n  } else throw e;\n}","preventionTips":["Reference worker names from shared constants used at both registration and start time.","Keep the MASTRA_WORKERS env filter in sync with registered worker names.","Log registered worker names at startup for easy verification."],"tags":["worker","lookup-failed","naming"],"backgroundTag":"resource-not-found","analyzedSha":"75dd419e613fe9c39f846ffc500716141b74fda6","analyzedAt":"2026-08-30T00:15:31.844Z","schemaVersion":2},"datasetVersion":"2026-08-30T03:17:51.788Z"}