feat(cli): add pi-mcp-adapter install support

[zh-xl-kang]

Summary

Add install/uninstall support for pi-mcp-adapter, a third-party tool that adds MCP support to the Pi coding agent.

Note: This is distinct from #534, which adds native Pi support via extensions. This PR specifically supports the pi-mcp-adapter workflow for users who have that adapter installed.

Context

Pi's official README states: "No MCP. Build CLI tools with READMEs (Skills), or build an extension that adds MCP support."

The pi-mcp-adapter is a community tool that bridges this gap by adding MCP support to Pi. This PR adds codebase-memory-mcp install/uninstall support for users who have pi-mcp-adapter installed.

Changes

• cli.c: Add install_pi_mcp_adapter() and uninstall_pi_mcp_adapter() functions

  • Detection checks for ~/.pi/agent/ (Pi agent directory) AND ~/.pi/agent/mcp.json (pi-mcp-adapter config file)
  • Install writes mcpServers entry to ~/.pi/agent/mcp.json
  • Uninstall removes the entry
  • Both functions follow the same error handling pattern as other installers

• cli.h: Add function declarations

• test_cli.c: Add test cases for install/uninstall lifecycle

Usage

Users who have both Pi agent and pi-mcp-adapter installed can now run:

codebase-memory-mcp install
# Detects pi-mcp-adapter presence and writes mcpServers entry

codebase-memory-mcp uninstall
# Removes the mcpServers entry

Users without pi-mcp-adapter should use #534's native extension-based integration instead.

Testing

• Verified install writes correct mcpServers entry to ~/.pi/agent/mcp.json
• Verified uninstall removes the entry cleanly
• Verified detection correctly identifies pi-mcp-adapter presence (requires both Pi agent dir and mcp.json file)

[DeusData]

Huge thanks for opening this PR and for the work you put into it.

The maintainer shop is currently full, so this may sit for a bit before it gets a proper review. We will come back to this as soon as possible with real feedback; I wanted to make sure it did not sit unacknowledged in the meantime.

[DeusData]

Thanks. This overlaps with #534 but uses a different Pi integration model. Before merge, maintainers should choose one path; please add an authoritative reference that Pi/pi-mcp-adapter consumes ~/.pi/agent/mcp.json using mcpServers.

[zh-xl-kang]

Thanks for the feedback! Here are the authoritative references:

Official Documentation: https://github.com/nicobailon/pi-mcp-adapter

The README explicitly states the file precedence, including:

<Pi agent dir>/mcp.json | Pi global override & compatibility imports (Default: ~/.pi/agent/mcp.json)

Regarding mcpServers format: pi-mcp-adapter reads standard MCP config files that use the mcpServers key structure, same as Claude Desktop, Cursor, and other MCP clients. The adapter automatically imports configs from these tools via /mcp setup or pi-mcp-adapter init.

Regarding #534: This PR focuses on install/uninstall support for pi-mcp-adapter itself (the adapter tool), not the Pi agent binary. The detection checks for ~/.pi/agent/ directory to identify Pi agent presence, then installs the adapter's MCP config into ~/.pi/agent/mcp.json.

Let me know if you need additional clarification on the integration model!

[zh-xl-kang]

After further analysis and discussion, I'm closing this PR in favor of #534 which takes the better architectural approach.

Reasoning:

• Pi officially does not support MCP (per its README: "No MCP. Build CLI tools with READMEs (Skills), or build an extension that adds MCP support.")
• feat(install): detect and configure pi coding agent #534 uses Pi's native extension mechanism — zero extra dependencies, works for all Pi users out of the box
• This PR only serves users who already have pi-mcp-adapter installed, which is a narrow audience
• Maintaining two integration paths for the same agent adds unnecessary complexity

Happy to review or help test #534 if needed. Thanks for the consideration, @DeusData.

[DeusData]

Thanks for the clarification and for closing this in favor of a single Pi integration path. We’ll evaluate #534 separately since it uses the native extension install path and needs a more focused review.