Letta · Capability

Letta API — Voice

Voice — low-latency voice-mode chat completions for agents (beta). 1 operations. Lead operation: Create Voice Chat Completions. Self-contained Naftiko capability covering one Letta business surface.

Letta API — Voice is a Naftiko capability published by Letta, one of 36 capabilities the APIs.io network indexes for this provider. It bundles 1 operation across the POST method rooted at /v1/voice-beta/{…}/chat/completions.

The capability includes 1 state-changing operation. Lead operation: Create Voice Chat Completions. Can be deployed as a REST endpoint, MCP tool, or Agent Skill via Naftiko.

Tagged areas include Letta, Stateful Agents, and Voice.

Run with Naftiko LettaStateful AgentsVoice

What You Can Do

POST
Create_voice_chat_completions — Create Voice Chat Completions
/v1/voice-beta/{agent-id}/chat/completions

MCP Tools

create-voice-chat-completions

Create Voice Chat Completions

Capability Spec

letta-voice.yaml Raw ↑ 
naftiko: "1.0.0-alpha2"

info:
  label: "Letta API — Voice"
  description: >-
    Voice — low-latency voice-mode chat completions for agents (beta). 1 operations. Lead operation: Create Voice Chat Completions. Self-contained Naftiko capability covering one Letta business surface.
  tags:
    - Letta
    - Stateful Agents
    - Voice
  created: "2026-05-08"
  modified: "2026-05-22"

binds:
  - namespace: env
    keys:
      LETTA_API_KEY: LETTA_API_KEY

capability:

  consumes:
    - type: http
      namespace: "letta-voice"
      baseUri: "https://api.letta.com"
      description: "Letta API — Voice business capability. Self-contained, no shared references."
      authentication:
        type: bearer
        token: "{{env.LETTA_API_KEY}}"
      resources:
        - name: "voice-beta-by-id-chat-completions"
          path: "/v1/voice-beta/{agent_id}/chat/completions"
          operations:
            - name: "create_voice_chat_completions"
              method: POST
              description: "Create Voice Chat Completions"
              inputParameters:
                - name: "agent_id"
                  in: path
                  type: string
                  required: true
                  description: "agent_id parameter"
                - name: "body"
                  in: body
                  type: object
                  required: true
                  description: "Request payload"
              outputRawFormat: json
              outputParameters:
                - name: result
                  type: object
                  value: "$."

  exposes:
    - type: rest
      namespace: "letta-voice-rest"
      port: 8080
      description: "REST adapter for Letta API — Voice. One Spectral-compliant resource per consumed operation."
      resources:
        - path: "/v1/voice-beta/{agent-id}/chat/completions"
          name: "voice-beta-by-id-chat-completions"
          description: "REST surface for voice-beta-by-id-chat-completions."
          operations:
            - method: POST
              name: "create_voice_chat_completions"
              description: "Create Voice Chat Completions"
              call: "letta-voice.create_voice_chat_completions"
              with:
                "agent_id": "rest.agent_id"
                "body": "rest.body"
              outputParameters:
                - type: object
                  mapping: "$."
    - type: mcp
      namespace: "letta-voice-mcp"
      port: 9090
      transport: http
      description: "MCP adapter for Letta API — Voice. One verb-noun tool per consumed operation."
      tools:
        - name: "create-voice-chat-completions"
          description: "Create Voice Chat Completions"
          hints:
            readOnly: false
            destructive: false
            idempotent: false
          call: "letta-voice.create_voice_chat_completions"
          with:
            "agent_id": "tools.agent_id"
            "body": "tools.body"
          outputParameters:
            - type: object
              mapping: "$."