API Reference

N.E.K.O. exposes a comprehensive API surface through FastAPI. All endpoints are served from the main server (default http://localhost:48911).

Base URL

http://localhost:48911

Authentication

The API does not require authentication for local access. API keys for LLM providers are managed separately through the Configuration system.

REST endpoints

Router	Prefix	Description
Config	/api/config	API keys, preferences, provider settings
Characters	/api/characters	Character CRUD, voice settings, microphone
Live2D	/api/live2d	Live2D model management, emotion mapping
VRM	/api/model/vrm	VRM model management, animations
Memory	/api/memory	Memory files, review configuration
Agent	/api/agent	Agent flags, tasks, health checks
Workshop	/api/steam/workshop	Steam Workshop items, publishing
System	/api	Emotion analysis, screenshots, utilities

WebSocket

Endpoint	Description
Protocol	Connection lifecycle and session management
Message Types	All client→server and server→client message formats
Audio Streaming	Binary audio format, interruption, resampling

Internal APIs

These are inter-service APIs not intended for external use:

Server	Description
Memory Server	Memory storage and retrieval (port 48912)
Agent Server	Agent task execution (port 48915)

Response format

All REST endpoints return JSON. Successful responses typically include the data directly. Error responses follow FastAPI's default format:

{
  "detail": "Error message describing what went wrong"
}

Content types

• application/json — Most endpoints
• multipart/form-data — File uploads (models, voice samples)
• audio/* — Voice preview responses