What causes "Method not implemented" in mastra-ai/mastra?

Override getApiClient() in your integration subclass to return the constructed API client

Method not implemented

Error message

Method not implemented

What it means

getApiClient on the base MastraIntegration class is a stub that throws 'Method not implemented' (note: without the trailing period of its siblings). Concrete integrations are expected to return their typed API client; the base class has none to give. It exists so the integration interface is uniform across integrations.

Source

Thrown at packages/core/src/integration/integration.ts:49

        };
      }, {});
    }
    return this.workflows;
  }

  /**
   * TOOLS
   */
  listStaticTools(_params?: ToolsParams): Record<string, ToolAction<any, any, any>> {
    throw new Error('Method not implemented.');
  }

  async listTools(_params?: ToolsParams): Promise<Record<string, ToolAction<any, any, any>>> {
    throw new Error('Method not implemented.');
  }

  async getApiClient(): Promise<ApiClient> {
    throw new Error('Method not implemented');
  }
}

View on GitHub (pinned to 75dd419e61)

Solutions

Override getApiClient() in your integration subclass to return the constructed API client
Feature-detect the override before calling, or maintain a registry of integrations known to expose clients
Construct the client yourself if you own the integration config (e.g. instantiate the generated OpenAPI client directly)
Wrap in try/catch where integrations are heterogeneous

Example fix

// before
class MyIntegration extends MastraIntegration {}
// after
class MyIntegration extends MastraIntegration {
  async getApiClient() {
    return new MyApiClient(this.config);
  }
}

Defensive patterns

Strategy: type-guard

Validate before calling

if (integration.getApiClient === MastraIntegration.prototype.getApiClient) {
  throw new Error(`${integration.name} does not expose an API client`);
}

Type guard

function exposesApiClient(integration) {
  return typeof integration.getApiClient === 'function' &&
    integration.getApiClient !== MastraIntegration.prototype.getApiClient;
}

Try / catch

try {
  const client = await integration.getApiClient();
} catch (e) {
  if (e.message.startsWith('Method not implemented')) {
    // integration has no client — handle clientless path
  } else {
    throw e;
  }
}

Prevention

Override getApiClient in integrations that have a backing API
Keep a registry/flag of which integrations expose clients
Do not assume client availability in generic integration loops
Note the base stub's message lacks a trailing period — don't match it too strictly

When it happens

Trigger: Calling await integration.getApiClient() on the base MastraIntegration or a subclass that never overrode it — e.g. code that assumes every integration exposes an API client and requests it for direct HTTP calls.

Common situations: A custom integration that only implements tools but not the client; generic integration loops fetching clients for logging or health checks; calling getApiClient during development of a new integration.

Related errors

AI-assisted analysis of mastra-ai/mastra@75dd419e61 (2026-08-30). Data as JSON: /api/errors/4684c34381224b37. Report an issue: GitHub.