claude-code-pi

Note: This extension spawns a fresh claude -p process for every model turn and does not maintain a persistent Claude Code session. See Notes and limitations for details on why caching and session persistence are intentionally disabled.

claude-code-pi registers a claude-code-cli provider in Pi and delegates every model call to the local Claude Code CLI with claude -p / --print.

This extension is intentionally a CLI bridge. It does not use the Anthropic SDK, direct HTTP APIs, or Pi's built-in Claude provider as a fallback. If claude -p is unavailable or fails, the Pi model turn fails with setup guidance instead of silently using another transport.

Requirements

• Pi Coding Agent
• Claude Code CLI installed and available on the same machine:

claude --version

• Claude Code authenticated/configured according to your local Claude Code setup.

Install

From this repository:

npm run install-extensions

Then restart Pi or run:

/reload

For one-off development testing without copying:

pi -e ./extensions/claude-code-pi/src/index.ts

Usage

Pick provider claude-code-cli from /model, or start Pi directly:

pi --provider claude-code-cli --model sonnet

Bundled model aliases mirror common Claude Code CLI --model aliases:

Pi provider	Pi model id	Passed to Claude Code
claude-code-cli	sonnet	claude -p --model sonnet
claude-code-cli	opus	claude -p --model opus
claude-code-cli	fable	claude -p --model fable

Print-mode smoke test:

pi -p --provider claude-code-cli --model sonnet "Reply with exactly OK"

Direct Claude Code transport check:

claude -p --model sonnet --no-session-persistence --tools "" "Reply with exactly OK"

Commands:

/claude-code-pi status
/claude-code-pi models
/claude-code-pi test
/claude-code-pi help

In the TUI, bare /claude-code-pi opens a read-only menu with the last in-memory Claude Code CLI status (or not checked), configuration-source presence, registered model count, and safe availability status (registered does not prove CLI model availability), plus navigation/help and Close. The panel never runs status probes, refresh/update/test/login/model calls, spawns Claude Code, or edits environment/model-file credentials. It shows only safe presence/status information: API keys, auth contents, credential values, URLs, stderr, and user emails are not displayed. Escape or Close exits the panel. Detail views show one short display segment per page (long records continue on the next page without losing text); use Previous/Next to navigate and Back to return to the sections. Non-TUI bare /claude-code-pi and every explicit subcommand keep their existing behavior.

Configuration

Environment variable	Description
CLAUDE_CODE_PI_BIN	Override the Claude Code executable path. Defaults to claude.
CLAUDE_CODE_PI_MODELS	Comma- or space-separated model aliases to register. Defaults to sonnet,opus,fable.
CLAUDE_CODE_PI_TIMEOUT_MS	Per-turn claude -p timeout in milliseconds. Defaults to 300000.
CLAUDE_CODE_PI_CONTEXT_WINDOW	Override the advertised context window in tokens. Defaults to 1000000 (current Claude aliases serve 1M-token context windows).

Example:

CLAUDE_CODE_PI_MODELS="sonnet,opus,claude-fable-5" pi

Thinking levels

Pi thinking levels map to Claude Code's --effort flag:

Pi thinking level	Passed to Claude Code
off / unset	no --effort flag
minimal, low	--effort low
medium	--effort medium
high	--effort high
xhigh	--effort xhigh

Images

Models advertise image input. When a turn contains images, the extension switches to the stream-json transport (--input-format stream-json --output-format stream-json --verbose) and sends images as base64 content blocks over stdin. Text-only turns keep the plain-text transport.

How it works

For each Pi model turn, the extension:

1. Serializes Pi's system prompt, conversation transcript, and available tool schemas into one text prompt.
2. Spawns the local Claude Code CLI with claude -p --model <selected> --no-session-persistence --tools "" --output-format text, plus --effort <level> when a thinking level is set.
3. Writes the serialized prompt (or a stream-json user message with base64 image blocks) to Claude Code over stdin.
4. Converts Claude Code stdout into a Pi assistant text message, or converts <pi_tool_call>{...}</pi_tool_call> markers into native Pi tool calls.
5. Emits a clear assistant error if the CLI is missing, exits non-zero, is aborted, or times out.

The extension disables Claude Code's own tools with --tools "". Pi tool schemas are included in the prompt, and explicit <pi_tool_call>{...}</pi_tool_call> markers are handed back to Pi so Pi executes tools through its normal pipeline.

Notes and limitations

• This is slower than native HTTP providers because a claude -p process starts for each model turn.
• Tool calling is prompt-bridged with <pi_tool_call>{...}</pi_tool_call> markers, so it is less reliable than native provider tool calling but still keeps execution in Pi.
• Image input requires the stream-json transport and is supported for base64 image blocks; availability checks use claude --version, so real model calls may still fail if local Claude Code auth or account access is not configured.
• No persistent session or context cache. The extension passes --no-session-persistence and spawns a new claude -p subprocess per turn. The full conversation transcript is re-serialized into the prompt each turn, so Claude Code's internal KV cache provides no benefit — the prefix is always re-sent. The only potential gain from a persistent process would be eliminating ~1–2 s of per-turn binary startup overhead, not token caching.

Anthropic terms of service analysis

A review of this extension's architecture against Anthropic's Consumer Terms of Service (§3.7), Commercial Terms of Service, and the Claude Code legal/compliance documentation (including the January–June 2026 enforcement wave and clarifications):

Rule	How this extension relates
No third-party harness spoofing / OAuth token extraction	✅ Compliant — spawns the genuine claude binary as a subprocess; never touches OAuth tokens, intercepts authentication, or impersonates the Claude Code harness
Binary must not be modified; built-in auth must not be disabled	✅ Runs the unmodified, published claude binary
Subscription automation must go through official CLI surfaces	⚠️ It does use the official CLI (claude -p), which Anthropic treats as first-party usage — but heavy headless/scripted claude -p on Pro/Max subscription auth is exactly the pattern Anthropic has flagged, and since June 2026 such usage draws from a dedicated Agent SDK credit pool rather than normal plan limits
Third-party products may not intermediate Claude for end users	⚠️ Fine as a personal tool run by the account owner; risky if distributed so that other users route their own subscriptions through it

Conclusion

Safe for personal use with your own credentials. The architecture deliberately does the compliant thing: a real claude -p subprocess per turn, no token extraction, no API fallback. This is the pattern Anthropic treats as first-party usage.

Residual risks:

1. Subscription auth + heavy automated/headless use matches the traffic pattern that led to account bans in early 2026, and now consumes the separate Agent SDK credit. Using an Anthropic API key inside Claude Code removes all ambiguity.
2. Distributing it to others who route their Pro/Max subscriptions through it edges toward "third-party product intermediating Claude" — the line Anthropic actively enforces (see the OpenCode and OpenClaw enforcement actions).
3. --permission-mode dontAsk means tool calls requested by the model execute through Pi without prompting — an operational safety consideration independent of the terms of service.

Verdict: safe for personal use with your own credentials; use an API key for heavy automation; do not ship it as a subscription-backed backend for other users.

Last reviewed against Anthropic's legal documentation published August 2026; terms and enforcement practices may change.