Mimo Free Opencode

An OpenCode provider plugin for Xiaomi MiMo Code's free mimo-auto model. It handles the anonymous bootstrap/JWT auth that the MiMo Code CLI does internally, so you get the free model inside OpenCode without a MiMo account, an API key, or running a separate proxy server.

Modeled on opencode-omniroute-auth, but keyless — MiMo's free tier authenticates anonymously.

How it differs from a proxy

Instead of pointing OpenCode at a local HTTP proxy, the plugin registers a mimo-free provider whose custom fetch does everything inline:

1. Keeps a pool of anonymous fingerprints, persisted to ~/.mimo-free/fingerprints.json (migrates the legacy client-fingerprint file).
2. Exchanges the active fingerprint for a short-lived anonymous JWT via POST /api/free-ai/bootstrap.
3. Rewrites the SDK's …/chat/completions call to MiMo's real …/chat endpoint.
4. Forces model: "mimo-auto", prepends the required MiMoCode system prompt, and attaches the JWT + CLI headers.
5. Refreshes the JWT ~5 min before expiry or on a 401/403, retrying once.
6. On 429 (rate limit) parks the current fingerprint with a cooldown, rotates to another fingerprint (minting a fresh one if the pool has room), re-bootstraps, and retries — up to MAX_429_RETRIES times.
7. When ENABLE_IP_ROTATION is set (on by default), routes outbound requests through a rotating pool of public HTTP proxies so MiMo sees a different egress IP on each rotation. Proxies are auto-tested, cached, and parked on cooldown after errors.

Install

Published to npm as mimo-free-opencode-plugin — public, installs anonymously, no token needed. Reference it from your opencode.json:

// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["mimo-free-opencode-plugin"]
}

Or load a local build directly:

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["./path/to/mimo-free-opencode-plugin/dist/index.js"]
}

Build the plugin first:

npm install
npm run build

Use

After OpenCode loads the plugin, pick the MiMo Auto (Free) model (mimo-free/mimo-auto) from the model list — that's it.

If your OpenCode version requires a provider to be "connected" before use, run:

/connect mimo-free

choose Anonymous — no key needed, and just press Enter at the key prompt. The plugin ignores whatever you type and authenticates anonymously.

Environment variables

• MIMO_BASE_URL — override the upstream base URL (default https://api.xiaomimimo.com).
• MAX_FINGERPRINTS — max fingerprints kept in the rotation pool (default 8).
• FP_COOLDOWN_MS — how long a rate-limited fingerprint is parked before reuse (default 3600000, 1h).
• MAX_429_RETRIES — rotation+retry attempts per request on 429 (default 3).

IP rotation (plugin + proxy server; set ENABLE_IP_ROTATION=0 to disable):

• PROXY_LIST_URL — URL to fetch HTTP proxy list from (default: SpeedX public list).
• MAX_PROXIES — max proxies in the rotation pool (default 10).
• PROXY_COOLDOWN_MS — cooldown for a proxy that returned an error (default 60000, 1 min).
• PROXY_TEST_TIMEOUT_MS — TCP connect timeout when testing proxies (default 3000).
• PROXY_LIST_MAX_AGE_MS — cache duration for downloaded proxy list (default 21600000, 6h).
• MAX_PROXY_RETRIES — proxy rotation retries per request (default 3).

Proxy server only (for deno run -A proxy/server.ts):

• PROXY_API_KEY — if set, callers must send Authorization: Bearer <key>.
• PORT — listen port (default 3000).

Public API

import MimoFreePlugin from "mimo-free-opencode-plugin";
// or named:
import { MimoFreePlugin } from "mimo-free-opencode-plugin";

Reusable runtime helpers (the same logic the plugin uses):

import {
  bootstrap,
  getJwt,
  createMimoFetch,
  ensureMimoSystemPrompt,
  PROVIDER_ID,
  MIMO_MODEL_ID,
} from "mimo-free-opencode-plugin/runtime";

Standalone proxy (optional)

The original OpenAI-compatible proxy server still lives at proxy/server.ts for anyone who wants a plain HTTP proxy instead of the plugin:

deno run -A proxy/server.ts

It serves POST /v1/chat/completions, GET /v1/models, and GET /health on port 3000 (override with PORT). Set PROXY_API_KEY to require callers to send Authorization: Bearer <key>.

The proxy server supports the same fingerprint pool and IP rotation features as the plugin — all environment variables listed above apply.

License

MIT — see LICENSE.