pi-claude-bridge

Pi extension that integrates Claude Code via the Agent SDK. Originally based on claude-agent-sdk-pi by Prateek Sunal.

1. Provider — Use Opus/Sonnet/Haiku as models in pi, with all tool calls flowing through pi's TUI
2. AskClaude tool — Delegate tasks or questions to Claude Code when using another provider

FYI: Anthropic announced and then unannounced a change to how you would be billed for tools that use the Agent SDK like this one. It currently uses your regular subscription quota just like Claude Code.

 

Install

pi install npm:pi-claude-bridge

Requires pi 0.86.1 or newer.

Provider

Use /model to select any Claude model in pi-ai's catalog, e.g. claude-bridge/claude-fable-5-1, claude-bridge/claude-opus-5, or claude-bridge/claude-haiku-4-5.

Behind the scenes, pi's tools are bridged to Claude Code but everything works like normal in pi. Bash commands get Claude Code's 120-second default timeout since pi's bash has none. Skills are forwarded to Claude Code's system prompt, and steering mid-turn reaches Claude at the next tool boundary.

The model list comes from pi-ai's Anthropic catalog automatically — when pi-ai adds a new Claude model, it appears in /model after updating the package, no bridge update needed. Dated snapshot ids (e.g. claude-opus-4-5-20251101) are not shown.

1M Context: Fable 5/5.1, Opus 5.5/5/4.8/4.7, and Sonnet 5.5/5 get 1M context. Opus 4.6 gets 1M only on a Max plan or with Extra Usage, and Sonnet 4.6 only with Extra Usage — set provider.plan and/or provider.longContextExtraUsage as described in Configuration.

AskClaude Tool

Deprecated: AskClaude is an opt-in legacy tool and may be removed in a future release. You should set askClaude.enabled to true (see Configuration) to use it. You can recreate similar functionality with one of the many Pi subagent extensions.

Configuration

Config: ~/.pi/agent/claude-bridge.json (global) or the project Pi config directory, usually .pi/claude-bridge.json (project; merged over global).

{
  "askClaude": {
    "enabled": true,
    "allowFullMode": true,
    "defaultIsolated": false,
    "description": "Custom tool description override"
  },
  "provider": {
    "plan": "max",
    "longContextExtraUsage": false,
    "strictMcpConfig": true,
    "pathToClaudeCodeExecutable": "/home/you/.nix-profile/bin/claude"
  }
}

askClaude:

• enabled — register the AskClaude tool (default false). If it's unset, the startup notice below points this out once.
• name — override the tool's pi-side name (default "AskClaude")
• label — override the TUI label (default "Ask Claude Code")
• description — override the tool description. Default when allowFullMode: true: "Delegate to Claude Code for a second opinion or analysis (code review, architecture questions, debugging theories), or to autonomously handle a task. Defaults to read-only mode — use full mode when the user wants to delegate a task that requires changes. Prefer to handle straightforward tasks yourself."
• defaultMode — "read" (default), "none", or "full"
• defaultIsolated — start each call in a fresh session (default false)
• allowFullMode — allow mode: "full"; set false to lock it out
• appendSkills — forward pi's skills block into the system prompt (default true)

provider:

• plan (default "pro") — set to "max" if you have a Max (or Team Premium/Enterprise) Anthropic plan. This enables Opus with 1M context.
• longContextExtraUsage — set to true to enable 1M context models even if they cost money through Extra Usage on your plan. It enables Sonnet 4.6 with 1M on every plan and Opus 4.6 with 1M on Pro. Not needed for Opus 4.7 or 4.8.
• forceTwoHundredK — array of model ids to pin to 200K context (bare id, no [1m] suffix). Use if pi-ai declares a model at 1M but Claude Code won't serve it on your plan.
• strictMcpConfig — block MCP servers from ~/.claude.json / .mcp.json (default true). Cloud MCP (Gmail/Drive via claude.ai OAuth) is always blocked.
• autoMemoryEnabled — enable Claude Code's auto-memory system (default false)
• pathToClaudeCodeExecutable — path to the claude binary. Useful if your OS/filesystem has the SDK's bundled musl/glibc binaries in a place where they can't run. For example, with Nix you can set the binary to e.g. "/home/you/.nix-profile/bin/claude".

Notices: the startup notice points out when provider.plan is unset and records startupNoticeShown in the global config. There's also a deprecation notice on first use of AskClaude that records its display date as askClaudeDeprecationShown.

Extension providers and models.json: pi's modelOverrides in ~/.pi/agent/models.json do not currently apply to extension-registered providers (like claude-bridge). Overriding contextWindow or other fields requires editing src/models.ts directly — to pin a model to 200K, use provider.forceTwoHundredK instead.

Tests

npm run test:unit for offline tests. npm test adds integration tests that hit APIs; set CLAUDE_BRIDGE_TESTING_ALT_MODEL in .env.test for the alt-provider smoke test.

Integration tests spawn real pi and Claude Code subprocesses and need write access to ~/.claude — a sandbox that blocks it makes --resume fail with No conversation found with session ID.

Debugging

Set CLAUDE_BRIDGE_DEBUG=1 to enable debug output:

• Bridge log at claude-bridge.log in pi's agent dir (PI_CODING_AGENT_DIR, default ~/.pi/agent) — provider calls, session sync decisions, tool results, CC stderr. Override location with CLAUDE_BRIDGE_DEBUG_PATH.
• Per-query CC CLI logs at `cc-cli-logs/--.log