What causes "Agent "${agent.id}" does not have memory configured" in mastra-ai/mastra?

Add memory to the agent: new Agent({ ..., memory: new Memory({ options: {...} }) })

mastra-ai/mastra · error · HTTPException

Agent "${agent.id}" does not have memory configured

Error message

Agent "${agent.id}" does not have memory configured

What it means

Creating a conversation requires the target agent to have Memory configured, since conversations are backed by memory threads. The handler resolves the agent via getAgentFromSystem, calls agent.getMemory(), and throws HTTP 400 if the agent has no memory instance.

Source

Thrown at packages/server/src/server/handlers/conversations.ts:65

  path: '/v1/conversations',
  responseType: 'json',
  bodySchema: createConversationBodySchema,
  responseSchema: conversationObjectSchema,
  summary: 'Create a conversation',
  description: 'Creates a new thread-backed conversation for agent-backed Responses API requests',
  tags: ['Responses'],
  requiresAuth: true,
  requiresPermission: MastraFGAPermissions.AGENTS_CREATE,
  handler: async ({ mastra, requestContext, agent_id, conversation_id, resource_id, title, metadata }) => {
    try {
      if (!mastra) {
        throw new HTTPException(500, { message: 'Mastra instance is required for conversations' });
      }

      const agent = await getAgentFromSystem({ mastra, agentId: agent_id });
      const memory = await agent.getMemory({ requestContext });
      if (!memory) {
        throw new HTTPException(400, { message: `Agent "${agent.id}" does not have memory configured` });
      }
      if (!(await getAgentMemoryStore({ agent, requestContext }))) {
        throw new HTTPException(400, { message: `Memory storage is not configured for agent "${agent.id}"` });
      }

      const threadId = conversation_id ?? randomUUID();
      const resourceId = getEffectiveResourceId(requestContext, resource_id) ?? threadId;
      const thread = await memory.createThread({
        threadId,
        resourceId,
        title,
        metadata,
      });

      return buildConversationObject({ thread });
    } catch (error) {
      return handleError(error, 'Error creating conversation');
    }

View on GitHub (pinned to 75dd419e61)

Solutions

Add memory to the agent: new Agent({ ..., memory: new Memory({ options: {...} }) })
Target a different agent_id that has memory configured
If conversations are not needed for this agent, use the stateless generate/stream APIs instead
Verify the agent ID resolves to the intended agent (typo check) via the agents list endpoint

Example fix

// before
const agent = new Agent({ name: 'bot', instructions: '...' });
// after
const agent = new Agent({ name: 'bot', instructions: '...', memory: new Memory({ storage }) });

Defensive patterns

Strategy: type-guard

Validate before calling

const agent = mastra.getAgent(agentId);
if (!agent || !(await agent.getMemory())) {
  throw new Error(`Agent "${agentId}" has no memory; conversation APIs unavailable`);
}

Type guard

function agentHasMemory(a: Agent | undefined): a is Agent & { getMemory(): Promise<Memory> } {
  return !!a && typeof a.getMemory === 'function' && aHasMemoryConfig(a);
}
// simpler runtime check:
async function memoryConfigured(a: Agent) { return (await a.getMemory()) != null; }

Try / catch

try {
  const conv = await client.createConversation({ agent_id });
} catch (e) {
  if (e.status === 400 && /does not have memory configured/.test(e.message)) {
    // fall back to stateless generate/stream for this agent
  }
  throw e;
}

Prevention

Give every agent that powers UI conversations a Memory instance
Validate agent definitions in a unit test (getMemory() non-null)
Keep agent IDs in one typed registry to avoid targeting the wrong agent
Document which agents are conversation-capable

When it happens

Trigger: POSTing to the create-conversation route with an agent_id whose Agent definition was constructed without a `memory` option, so getMemory() returns undefined/null.

Common situations: Agents built for stateless use cases being targeted by the playground/API conversation features; memory removed from an agent during refactoring; calling create-conversation against the wrong agent ID; new Agent({}) without memory in a minimal setup.

Related errors

AI-assisted analysis of mastra-ai/mastra@75dd419e61 (2026-08-30). Data as JSON: /api/errors/d1b6254b258bde65. Report an issue: GitHub.