copilot-reverse

copilot-reverse

Use the GitHub Copilot subscription you already pay for as a local Claude Code / Codex backend. No new API keys. No per-token bills. One terminal app.

  ┌─────────────┐        ┌───────────────────┐        ┌─────────────┐
  │ Claude Code │ ─────▶ │  copilot-reverse  │ ─────▶ │   Copilot   │
  │   / Codex   │  local │  (your machine)   │  proxy │  (your sub) │
  └─────────────┘        └───────────────────┘        └─────────────┘

Disclaimer: The GitHub Copilot integration uses community-documented, unofficial endpoints, for use with your own Copilot subscription only. It may break if GitHub changes these endpoints.

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60-second start

npx copilot-reverse

1. It asks you to log in to GitHub (device code — paste a code in your browser). One time only.
2. The terminal app launches. You'll see a prompt and a status bar.
3. In the app, type:

   /setup-claude

   Pick a model (e.g. claude-opus-4.8 (1M)), choose global, done.
4. Open a new terminal and run claude. It's now talking to Copilot through copilot-reverse.

That's it. Codex users: run /setup-codex instead.

Here's the app itself — a prompt, a live status bar, and slash-command autocomplete:

 ✳ copilot-reverse                                                       worker: ready

 Type a message to chat with the assistant, or /help for commands.
╭─────────────────────────────────────────────────────────────────────────────────────╮
│ › /setup                                                                              │
╰─────────────────────────────────────────────────────────────────────────────────────╯
  ❯ /setup-claude   print Claude Code config
    /setup-codex    print Codex/OpenAI config
    /setup-status   show configured endpoints
    ↑↓ navigate · tab complete · enter run
 model claude-opus-4.8  ·  daemon ready  ·  claude u:✓ p:○  codex u:✓ p:○  ·  /help

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What can I do in the app?

Just talk to it — it understands plain English and will do the work for you:

"list models" → shows every model + its context window "set up claude" → asks scope (global/project) + model, then configures Claude Code "is the worker healthy?" → runs a health check "why did my last request fail?" → shows the error (incl. cut-short stream runaways)

Prefer commands? Type / to see them all. The essentials:

Command	What it does
/setup-claude · /setup-codex	Point Claude Code / Codex at copilot-reverse
/model	Switch the chat model (1M-context models marked)
/status · /doctor	Is everything healthy? (/status shows each client's scope + model)
/logs · /metrics	What ran, what failed, and why
/dashboard	Open a live web dashboard in your browser
/report	File a pre-filled bug report (diagnostics only — no prompts)
/reset-claude · /reset-codex	Undo setup, restore original config
/login · /logout	Sign in to GitHub (device-code) · sign out (remove token)
/help · /quit	List commands · exit

The live dashboard

/dashboard opens a self-refreshing web view of everything happening through the proxy — worker health, request volume, and (most useful) recent errors with their real messages:

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Connect your own tools

Already have something that speaks OpenAI or Anthropic? Point it here:

• OpenAI-compatible: http://127.0.0.1:7891/openai
• Anthropic-compatible: http://127.0.0.1:7891/anthropic

Any API key value works locally (it's your machine). Example:

export ANTHROPIC_BASE_URL=http://127.0.0.1:7891/anthropic
export ANTHROPIC_API_KEY=local
claude

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The status bar, decoded

The bottom line of the app tells you everything at a glance:

model claude-opus-4.8  ·  daemon ready  ·  claude u:✓ p:○  codex u:○ p:○  ·  /help

• worker / daemon — green ready means the proxy is up and self-healing.
• claude u:✓ p:○ — Claude Code is configured at the user (global) level, not in this project. Read live from your real config files.

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Troubleshooting

"context 100%" or /compact fails in Claude Code Re-run /setup-claude and pick a 1M model (e.g. claude-opus-4.8 (1M)). copilot-reverse writes the right context-window hint so the client stops assuming a small window. Then restart Claude Code.

"GitHub login expired" Your Copilot session lapsed. You don't need to restart anything — when a chat fails, copilot-reverse detects it and tells you right there:

assistant error: 401 authentication_error: GitHub login expired
  ↳ your GitHub login looks expired — run /login to sign in again

Just type /login, complete the device-code prompt, and you're back — the worker reloads the new token automatically. (Switching accounts? /logout first, then /login.)

A request failed and I don't know why Type /logs (or ask "why did that fail?"). Every failure is captured with its real upstream message. Still stuck? /report opens a pre-filled GitHub issue with diagnostics — never your prompt content.

Want to undo everything /reset-claude and /reset-codex remove exactly the keys copilot-reverse added and leave the rest of your config untouched.

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Good to know

• Your data stays local. The app proxies between your editor and Copilot on 127.0.0.1. Your GitHub token lives only in ~/.copilot-reverse/creds.json on your own disk.
• It heals itself. If the proxy crashes, the supervisor restarts it with backoff and records why.
• It never freezes. If a model degenerates (loops on one token, never stops), the proxy cuts the stream cleanly as max_tokens and tags it — /report then files a prefilled issue so it's easy to flag.
• Tunable. ~/.copilot-reverse config covers ports, restart backoff, and the GitHub-token heartbeat interval; defaults are sensible, override only if needed.
• Unofficial endpoints. This uses community-documented Copilot endpoints with your own subscription. It may break if GitHub changes them — that's the trade-off for not needing extra keys.

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Architecture

Three processes, one terminal app:

• TUI (Ink) — the copilot-reverse process: REPL + slash commands + a claude-agent-sdk assistant (which dogfoods copilot-reverse's own Anthropic endpoint).
• Supervisor (:7890) — control API + SQLite + self-healing worker supervision.
• Worker (:7891) — OpenAI /openai/chat/completions + Anthropic /anthropic/v1/messages → Copilot, with tool-use translation both ways. Each protocol also serves a …/models discovery endpoint.

Development

Requires Node >=20.

npm install && npm test && npm run build

End-to-end tests

The e2e/ folder holds cross-module end-to-end scenarios (real worker + supervisor + TUI wiring, fake Copilot provider). The case catalog is e2e/cases.md and the latest run is e2e/RESULTS.md.

Every code change must keep the full e2e suite green. npm test runs it (the suite is included in the default vitest run); npm run test:e2e runs only the e2e cases. After a change, re-run and update e2e/RESULTS.md.

Test notes

• TUI input tests (tests/tui/app.test.tsx): the test waits ~30 ms after render() before writing to stdin. This is not flakiness padding — Ink's useInput subscribes to stdin asynchronously after mount, so writes issued in the same tick as render() are dropped. The delay lets the subscription attach; assertions are otherwise unchanged.

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Questions or bugs? Use /report from inside the app, or open an issue on GitHub. Happy hacking.