---
summary: "Expose an OpenAI-compatible /v1/chat/completions HTTP endpoint from the Gateway"
read_when:
  - Integrating tools that expect OpenAI Chat Completions
title: "OpenAI Chat Completions"
---

# OpenAI Chat Completions (HTTP)

SKYKOI’s Gateway can serve a small OpenAI-compatible Chat Completions endpoint.

This endpoint is **disabled by default**. Enable it in config first.

- `POST /v1/chat/completions`
- Same port as the Gateway (WS + HTTP multiplex): `http://<gateway-host>:<port>/v1/chat/completions`

Under the hood, requests are executed as a normal Gateway koi run (same codepath as `SKYKOI koi`), so routing/permissions/config match your Gateway.

## Authentication

Uses the Gateway auth configuration. Send a bearer token:

- `Authorization: Bearer <token>`

Notes:

- When `gateway.auth.mode="token"`, use `gateway.auth.token` (or `SKYKOI_GATEWAY_TOKEN`).
- When `gateway.auth.mode="password"`, use `gateway.auth.password` (or `SKYKOI_GATEWAY_PASSWORD`).

## Choosing an koi

No custom headers required: encode the koi id in the OpenAI `model` field:

- `model: "SKYKOI:<koiId>"` (example: `"SKYKOI:main"`, `"SKYKOI:beta"`)
- `model: "koi:<koiId>"` (alias)

Or target a specific SKYKOI koi by header:

- `x-SKYKOI-koi-id: <koiId>` (default: `main`)

Advanced:

- `x-SKYKOI-session-key: <sessionKey>` to fully control session routing.

## Enabling the endpoint

Set `gateway.http.endpoints.chatCompletions.enabled` to `true`:

```json5
{
  gateway: {
    http: {
      endpoints: {
        chatCompletions: { enabled: true },
      },
    },
  },
}
```

## Disabling the endpoint

Set `gateway.http.endpoints.chatCompletions.enabled` to `false`:

```json5
{
  gateway: {
    http: {
      endpoints: {
        chatCompletions: { enabled: false },
      },
    },
  },
}
```

## Session behavior

By default the endpoint is **stateless per request** (a new session key is generated each call).

If the request includes an OpenAI `user` string, the Gateway derives a stable session key from it, so repeated calls can share an koi session.

## Streaming (SSE)

Set `stream: true` to receive Server-Sent Events (SSE):

- `Content-Type: text/event-stream`
- Each event line is `data: <json>`
- Stream ends with `data: [DONE]`

## Examples

Non-streaming:

```bash
curl -sS http://127.0.0.1:18789/v1/chat/completions \
  -H 'Authorization: Bearer YOUR_TOKEN' \
  -H 'Content-Type: application/json' \
  -H 'x-SKYKOI-koi-id: main' \
  -d '{
    "model": "SKYKOI",
    "messages": [{"role":"user","content":"hi"}]
  }'
```

Streaming:

```bash
curl -N http://127.0.0.1:18789/v1/chat/completions \
  -H 'Authorization: Bearer YOUR_TOKEN' \
  -H 'Content-Type: application/json' \
  -H 'x-SKYKOI-koi-id: main' \
  -d '{
    "model": "SKYKOI",
    "stream": true,
    "messages": [{"role":"user","content":"hi"}]
  }'
```