Letta MCP Server

Instructions

Implementation Reference

• src/tools/agents/retrieve-agent.js:4-34 (handler)

  The main handler function that implements the logic for the 'retrieve_agent' tool. It fetches the full state of an agent by ID using the server's API and returns it as JSON text content.

  export async function handleRetrieveAgent(server, args) {
      if (!args?.agent_id) {
          server.createErrorResponse('Missing required argument: agent_id');
      }
  
      try {
          const headers = server.getApiHeaders();
          const agentId = encodeURIComponent(args.agent_id);
  
          // Use the specific endpoint from the OpenAPI spec
          const response = await server.api.get(`/agents/${agentId}`, { headers });
          const agentState = response.data; // Assuming response.data is the AgentState object
  
          return {
              content: [
                  {
                      type: 'text',
                      text: JSON.stringify({
                          agent: agentState,
                      }),
                  },
              ],
          };
      } catch (error) {
          // Handle potential 404 if agent not found, or other API errors
          if (error.response && error.response.status === 404) {
              server.createErrorResponse(`Agent not found: ${args.agent_id}`);
          }
          server.createErrorResponse(error);
      }
  }

• src/tools/agents/retrieve-agent.js:39-53 (schema)

  The tool definition including name, description, and input schema for 'retrieve_agent'.

  export const retrieveAgentDefinition = {
      name: 'retrieve_agent',
      description:
          'Get the full state of a specific agent by ID. Similar to get_agent_summary but returns complete details. Use list_agents to find agent IDs.',
      inputSchema: {
          type: 'object',
          properties: {
              agent_id: {
                  type: 'string',
                  description: 'The ID of the agent to retrieve',
              },
          },
          required: ['agent_id'],
      },
  };

• src/tools/index.js:183-184 (registration)

  Switch case in the tool call handler that routes 'retrieve_agent' calls to the handleRetrieveAgent function.

  case 'retrieve_agent':
      return handleRetrieveAgent(server, request.params.arguments);

• src/tools/index.js:119-119 (registration)

  Inclusion of retrieveAgentDefinition in the allTools array used to register tool definitions with the MCP server.

  retrieveAgentDefinition,

• src/tools/index.js:6-6 (registration)

  Import of the handler and definition for 'retrieve_agent'.

  import { handleRetrieveAgent, retrieveAgentDefinition } from './agents/retrieve-agent.js';