{"record":{"id":"4bbc0e52ddc01196","repo":"mastra-ai/mastra","slug":"subconscious-semantic-knowledge-requires-an-embedd","errorCode":null,"errorMessage":"Subconscious semantic knowledge requires an embedder. Pass an `embedder` option to Memory.","messagePattern":"Subconscious semantic knowledge requires an embedder\\. Pass an `embedder` option to Memory\\.","errorType":"validation","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"packages/memory/src/index.ts","lineNumber":519,"sourceCode":"    const omConfig = normalizeObservationalMemoryConfig(mergedConfig.observationalMemory);\n    if (omConfig?.retrieval && typeof omConfig.retrieval === 'object' && omConfig.retrieval.vector) {\n      if (!this.vector) {\n        throw new Error(\n          '`retrieval: { vector: true }` requires a vector store. Pass a `vector` option to your Memory instance.',\n        );\n      }\n      if (!this.embedder) {\n        throw new Error(\n          '`retrieval: { vector: true }` requires an embedder. Pass an `embedder` option to your Memory instance.',\n        );\n      }\n    }\n    if (omConfig?.experimental_subconscious) {\n      if (!this.vector) {\n        throw new Error('Subconscious semantic knowledge requires a vector store. Pass a `vector` option to Memory.');\n      }\n      if (!this.embedder) {\n        throw new Error('Subconscious semantic knowledge requires an embedder. Pass an `embedder` option to Memory.');\n      }\n    }\n  }\n\n  private async getKnowledgeStore(): Promise<KnowledgeStorage> {\n    const store = await this.storage.getStore('knowledge');\n    if (!store) {\n      throw new Error(`Knowledge storage domain is not available on ${this.storage.constructor.name}`);\n    }\n    return store;\n  }\n\n  public async getKnowledgeSemanticIndex(): Promise<KnowledgeSemanticIndexCoordinator> {\n    if (!this.vector || !this.embedder) {\n      throw new Error('Subconscious semantic knowledge requires both a vector store and an embedder.');\n    }\n    this._knowledgeSemanticIndex ??= this.getKnowledgeStore().then(\n      knowledge =>","sourceCodeStart":501,"sourceCodeEnd":537,"githubUrl":"https://github.com/mastra-ai/mastra/blob/75dd419e613fe9c39f846ffc500716141b74fda6/packages/memory/src/index.ts#L501-L537","documentation":"The experimental_subconscious embeds knowledge for semantic lookup, so besides a vector store it requires an embedder. The Memory constructor checks `this.embedder` when `experimental_subconscious` is configured and throws if it is missing.","triggerScenarios":"`new Memory({ vector, options: { observationalMemory: { experimental_subconscious: new Subconscious({...}) } } })` constructed with a vector store but no `embedder` option.","commonSituations":"Vector store added but embedder omitted when enabling the subconscious; embedder removed during refactoring while the subconscious stayed enabled; assuming subconscious uses the agent's LLM instead of a dedicated embedding model.","solutions":["Pass an `embedder` option (e.g. FastEmbed, OpenAI embeddings) to the Memory constructor","Remove experimental_subconscious if not needed","Verify embedder credentials/model name are valid for the provider"],"exampleFix":"// before\nnew Memory({ vector, options: { observationalMemory: { experimental_subconscious: sub } } })\n// after\nnew Memory({ vector, embedder: new FastEmbed(), options: { observationalMemory: { experimental_subconscious: sub } } })","handlingStrategy":"validation","validationCode":"if (opts.options?.observationalMemory?.experimental_subconscious && !opts.embedder) {\n  throw new Error('experimental_subconscious requires an embedder option on Memory');\n}","typeGuard":null,"tryCatchPattern":"try {\n  const memory = new Memory(opts);\n} catch (err) {\n  if (err instanceof Error && err.message.includes('requires an embedder')) {\n    // add embedder and rebuild Memory\n  } else throw err;\n}","preventionTips":["Configure embedder whenever subconscious is enabled","Use a Memory config builder that couples subconscious with vector+embedder","Confirm embedding provider credentials per environment","Avoid removing embedder options during refactors without re-running construction tests"],"tags":["configuration","embedder","subconscious","validation"],"backgroundTag":"missing-embedder-config","analyzedSha":"75dd419e613fe9c39f846ffc500716141b74fda6","analyzedAt":"2026-08-30T00:15:31.844Z","schemaVersion":2},"datasetVersion":"2026-08-30T03:17:51.788Z"}