mastra-ai/mastra · critical · Error

Memory requires a storage provider to function. Add a storag

Error message

Memory requires a storage provider to function. Add a storage configuration to Memory or to your Mastra instance.

https://mastra.ai/en/docs/memory/overview

What it means

Memory needs a storage adapter to persist threads and messages; the lazy `storage` getter throws this Error when accessed while `this._storage` is undefined. Storage can be attached directly to Memory or inherited from the Mastra instance. The getter exists so Memory fails with a clear actionable message instead of a confusing null dereference later.

Source

Thrown at packages/core/src/memory/memory.ts:234

  }

  /**
   * Internal method used by Mastra to register itself with the memory.
   * @param mastra The Mastra instance.
   * @internal
   */
  __registerMastra(mastra: Mastra): void {
    this.#mastra = mastra;
  }

  protected _hasOwnStorage = false;
  get hasOwnStorage() {
    return this._hasOwnStorage;
  }

  get storage() {
    if (!this._storage) {
      throw new Error(
        `Memory requires a storage provider to function. Add a storage configuration to Memory or to your Mastra instance.

https://mastra.ai/en/docs/memory/overview`,
      );
    }
    return this._storage;
  }

  public setStorage(storage: MastraCompositeStore) {
    this._storage = augmentWithInit(storage);
  }

  public setVector(vector: MastraVector) {
    this.vector = vector;
  }

  public setEmbedder(
    embedder: EmbeddingModelId | MastraEmbeddingModel<string>,

View on GitHub (pinned to 75dd419e61)

Solutions

Add a storage adapter to the Memory config, e.g. storage: new LibSQLStore({ url: 'file:memory.db' }).
Or attach Memory to a Mastra instance that has storage configured, so Memory inherits it.
Ensure the code path that accesses memory.storage runs only after the Memory instance is fully constructed/registered.

Example fix

// before
const memory = new Memory({ options: { lastMessages: 10 } });

// after
const memory = new Memory({
  storage: new LibSQLStore({ url: 'file:memory.db' }),
  options: { lastMessages: 10 },
});

Defensive patterns

Strategy: validation

Validate before calling

function ensureMemoryStorage(memory) {
  if (!memory.hasOwnStorage) {
    // only safe if Memory is registered on a Mastra instance with storage
    throw new Error('Memory has no storage attached; pass storage or register on Mastra with storage');
  }
}

Type guard

function hasStorage(m) { return typeof m.hasOwnStorage === 'boolean' && m.hasOwnStorage; }

Prevention

Configure storage on the Mastra instance once and let all Memory instances inherit it.
Never construct Memory with options-only config outside tests.
Guard direct memory.storage access behind a helper that validates presence first.

When it happens

Trigger: Accessing memory.storage (directly or via internal operations like recall, thread creation, saveMessages) on a Memory instance constructed with no storage config and not attached to a Mastra instance that has storage.

Common situations: Standalone Memory usage in tests or scripts where a storage adapter was never configured; constructing `new Memory({ options })` with only semantic-recall/working-memory options; forgetting that Mastra instance-level storage only applies when Memory is registered on that instance.

Related errors

AI-assisted analysis of mastra-ai/mastra@75dd419e61 (2026-08-30). Data as JSON: /api/errors/479297943b791a2b. Report an issue: GitHub.