pi-claude-oauth-adapter

Anthropic OAuth / Claude Code compatibility adapter for Pi.

Install: pi install npm:pi-claude-oauth-adapter

This package patches Anthropic OAuth / Claude Pro/Max sessions in Pi. It strips the docs-only Pi section out of the system prompt, removes the Claude Code identity block, reinjects Pi docs context outside the system prompt when needed, and makes sure the Claude billing header is present for OAuth requests.

What's new in 0.2.0

• The injected Claude billing header now tracks Claude Code 2.1.226; cch=00000 is only included for first-party Anthropic requests.
• The quota probe now uses Claude Code's external CLI user agent, sends only the OAuth beta for the Haiku probe, and tries GET /api/oauth/usage before falling back to a tiny messages request.
• Unified usage-limit parsing now understands 7d_oi / Fable 5 limits, overage utilization, overage in-use state, usage-credit wording, and grace-window warnings.

What's new in 0.1.4

• The injected Claude billing header now tracks Claude Code 2.1.126 (cc_version hash input, entrypoint, fixed cch=00000, optional cc_workload).
• Unified usage-limit parsing now preserves the latest anthropic-ratelimit-unified-fallback and anthropic-ratelimit-unified-upgrade-paths fields.
• 429 responses that include representative-claim or overage headers but omit anthropic-ratelimit-unified-status are treated as rejected, matching Claude Code's current fallback path.

What's new in 0.1.3

• Pi now surfaces Claude unified usage-limit state on the real 429 path, including a follow-up quota check that rewrites generic Anthropic rate-limit failures into Claude-style messages like You've hit your limit · resets 10:30pm (Asia/Colombo).
• The injected Claude billing header now matches Claude Code 2.1.118 semantics more closely: updated cc_version, fixed cch=00000, and optional cc_workload passthrough.
• The adapter still exposes claude-oauth-ready and claude-oauth-issue status keys so Pi runtimes can suppress generic Anthropic subscription warnings only when the adapter is actually healthy.
• On 429s, the adapter patches Anthropic's generic rate_limit_error into the resolved Claude usage-limit message so Pi's auto-retry logic stops thrashing.

The last point depends on the Pi runtime version. The package publishes the readiness signal; Pi still has to consume it.

When this package does anything

It only activates when both of these are true:

• the selected provider is anthropic
• Pi is using Anthropic OAuth / subscription auth

If you use ANTHROPIC_API_KEY only, this package stays inactive.

Install

From npm

pi install npm:pi-claude-oauth-adapter
pi list

Then inside Pi:

1. run /login
2. choose Claude Pro/Max
3. pick an Anthropic model in /model
4. start using Pi normally

From a local checkout

If you use this repo directly, add the local package path to Pi settings:

{
  "packages": [
    "../../Developer/dotfiles-agents/packages/pi-claude-oauth-adapter"
  ]
}

./setup.sh in this repo already provisions that path when the active Pi settings symlink points at this checkout.

Verify it is active

In an Anthropic OAuth session, the package should either:

• show ✓ Claude OAuth ready before the first request
• show ✓ Claude OAuth active after a normalized Anthropic OAuth request
• show a real Claude usage status like You've hit your limit · resets 10:30pm (Asia/Colombo) when Anthropic rejects the request and the adapter resolves quota state via the follow-up check
• show ⚠ Claude OAuth setup if the adapter is enabled but missing the docs context it needs

If you are using API-key auth instead of OAuth, none of those statuses should appear.

Config

Environment variables:

• PI_CLAUDE_OAUTH_REINJECT_SCOPE=never|always|pi-only
  • default: pi-only
• PI_CLAUDE_OAUTH_REINJECT_MODE=prepend-custom-message|append-custom-message|user-reminder|none
  • default: prepend-custom-message
• PI_CLAUDE_OAUTH_LOG_FILE=/path/to/log.jsonl
  • optional debug logging
• PI_CLAUDE_OAUTH_DOCS_FILE=/path/to/pi-docs-only.txt
  • optional docs fallback override
• PI_CLAUDE_CODE_VERSION=...
• PI_CLAUDE_CODE_ENTRYPOINT=...
• PI_CLAUDE_CODE_WORKLOAD=...
• PI_CLAUDE_CODE_SUBSCRIPTION_TYPE=...
  • optional billing-header / footer-label overrides

For most users, no env vars are required.

If you want the stripped docs context available for every request instead of only Pi-related prompts:

PI_CLAUDE_OAUTH_REINJECT_SCOPE=always pi

Release notes

See CHANGELOG.md.

Maintainer release flow

cd packages/pi-claude-oauth-adapter
npm pack --dry-run
npm publish --access public

Or from repo root:

npm publish ./packages/pi-claude-oauth-adapter --access public

Notes

• This package does not implement Anthropic auth itself. Pi already has built-in Anthropic OAuth support.
• This package is the compatibility layer on top of Pi's Anthropic OAuth flow.
• It is designed to work both with already-patched Pi builds and older/provider builds that still need the billing header injected at request time.
• Full user-agent / provider-header parity with Claude Code does not belong in this package. Pi's provider override API is provider-wide, not OAuth-scoped, so that part should land in @mariozechner/pi-ai instead of changing all Anthropic traffic from here.