pi-claude-oauth-adapter

Use a Claude Pro or Max subscription with Pi.

pi install npm:pi-claude-oauth-adapter

This extension adapts Pi's built-in Anthropic OAuth flow to the request format expected by Claude's subscription backend. It does not implement OAuth or bypass usage limits.

Setup

1. Install the package.
2. Start Pi and run /login.
3. Choose Claude Pro/Max.
4. Select an Anthropic model with /model.

The footer should show ✓ Claude OAuth ready, then ✓ Claude OAuth active after the first request.

The adapter runs only when both conditions are true:

• the provider is anthropic
• Pi is using OAuth

Requests using ANTHROPIC_API_KEY are unchanged.

What it changes

flowchart LR
    A[Pi request] --> B{Anthropic OAuth?}
    B -- No --> C[Send unchanged]
    B -- Yes --> D[Normalize prompt and billing header]
    D --> E[Anthropic]
    E -- 429 --> F[Resolve quota and reset time]
    E -- Success --> G[Claude response]

For Anthropic OAuth requests, the adapter:

• removes Pi's docs block and any conflicting Claude Code identity block from the system prompt
• reinjects Pi docs as hidden context when the user asks about Pi
• adds or updates the Claude billing header
• turns generic 429 responses into Claude-style limit and reset messages

On an ambiguous 429, it checks Anthropic's OAuth usage endpoint and falls back to a minimal Haiku request. Results are cached for 30 seconds.

Status

Footer text	Meaning
✓ Claude OAuth ready	OAuth was detected and setup is valid.
✓ Claude OAuth active	A request was normalized.
⚠ Claude OAuth setup	Required Pi docs context could not be found.
You've hit your ... limit	Anthropic reported a subscription limit.

No status appears for API-key sessions or other providers.

Configuration

No configuration is required for normal use.

Variable	Default	Purpose
PI_CLAUDE_OAUTH_REINJECT_SCOPE	pi-only	pi-only, always, or never
PI_CLAUDE_OAUTH_REINJECT_MODE	prepend-custom-message	prepend-custom-message, append-custom-message, user-reminder, or none
PI_CLAUDE_OAUTH_DOCS_FILE	unset	Fallback file containing Pi docs context
PI_CLAUDE_OAUTH_LOG_FILE	unset	JSONL debug log path
PI_CLAUDE_CODE_VERSION	bundled version	Pin the Claude Code version in request metadata (disables version learning)
PI_CLAUDE_OAUTH_VERSION_CHECK	1	Set to 0 to stop refreshing the advertised Claude Code version from the npm registry
PI_CLAUDE_OAUTH_CLIENT_HEADERS	1	Set to 0 to stop sending user-agent / x-app / x-claude-code-session-id
PI_CLAUDE_CODE_ENTRYPOINT	pi	Billing-header entrypoint
PI_CLAUDE_CODE_WORKLOAD	unset	Optional workload metadata
PI_CLAUDE_CODE_SUBSCRIPTION_TYPE	unset	Plan type used for limit labels

Example:

PI_CLAUDE_OAUTH_REINJECT_SCOPE=always pi

Debug logs may contain prompt excerpts and request metadata. Review and redact them before sharing.

Install from source

git clone https://github.com/minzique/pi-claude-oauth-adapter.git
pi install ./pi-claude-oauth-adapter

To test a checkout without installing it:

pi -e ./pi-claude-oauth-adapter

Troubleshooting

If no status appears, check pi list, select an Anthropic model, and log in through Claude Pro/Max instead of an API key.

If ⚠ Claude OAuth setup appears, provide the docs context explicitly:

PI_CLAUDE_OAUTH_DOCS_FILE=/absolute/path/to/pi-docs-only.txt pi

To collect a debug log:

PI_CLAUDE_OAUTH_LOG_FILE="$PWD/claude-oauth-debug.jsonl" pi

Report bugs on GitHub. See the changelog for release notes.

Development

npm install
npm run check
npm pack --dry-run

The extension entry point is extensions/index.ts.

Security

Pi extensions run with your user account's permissions. Review third-party extension code before installing it.

This adapter sends no telemetry and writes no logs unless PI_CLAUDE_OAUTH_LOG_FILE is set. Quota checks go to the configured Anthropic endpoint. The first-party OAuth usage endpoint is used only for api.anthropic.com sessions.

This project is unofficial and is not affiliated with Anthropic.

License

MIT