feat: add claw-acp — ACP server bridge for IDE integration

[joka-7]

Demo

WebStorm AI Chat using NanoClaw as the agent backend via ACP — @file mention
attaches the file content, which is fetched from the IDE via fs/read_text_file
and forwarded to the NanoClaw agent in the prompt.

Summary

Adds claw-acp, a utility skill that makes NanoClaw available as an ACP server — so IDEs like WebStorm, Zed, and acpx can use NanoClaw as their AI backend via the Agent Client Protocol.

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How it works

IDE (WebStorm / Zed / acpx)
  │  spawns claw-acp as a subprocess
  │  ACP JSON-RPC 2.0 over stdio
  ▼
claw-acp  (.claude/skills/add-acp-server/scripts/claw-acp.ts)
  │  JSON lines over Unix socket
  ▼
NanoClaw CLI channel  (data/cli.sock)
  │  routes to wired agent group
  ▼
Agent container → Claude → response
  │
  └──▶  back through CLI socket → claw-acp → IDE

No NanoClaw host changes. claw-acp is a pure bridge on top of the existing CLI channel — install the skill, add one config file to your IDE, done.

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ACP server vs ACP client

NanoClaw already has an ACP client provider (feature/acp-agent-client-protocol) — where NanoClaw connects out to an external ACP agent and uses it as the container's AI backend.

This PR is the opposite direction: the IDE connects in to NanoClaw.

	ACP client	ACP server (this PR)
NanoClaw's role	ACP client	ACP server
Who initiates	NanoClaw → external agent	IDE → NanoClaw
What it changes	Host + container provider code	Standalone bridge script only
Skill type	Feature skill	Utility skill
Config	agent_provider: "acp-client" on agent group	~/.jetbrains/acp.json or Zed settings

Both can run simultaneously — the IDE connects to NanoClaw via the server bridge, while NanoClaw's agent containers can still connect out to external ACP agents as their AI backend.

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Supported ACP methods

Method	Status	Notes
initialize	✅ Full	Returns promptCapabilities, serverInfo, authMethods
session/new	✅ Full	Generates UUID session ID
session/prompt	✅ Full	Non-streaming; full response in one session/update chunk
session/cancel	✅ Full	Closes CLI socket
session/close	✅ Full	Closes CLI socket
fs/read_text_file	✅ Full	line/limit support; sandboxed to $HOME or NANOCLAW_FS_ROOT
fs/write_text_file	❌ Not supported	—

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Install

/add-acp-server

Then add one config file to your IDE. See SKILL.md for JetBrains, Zed, and acpx config examples.

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Files

File	Purpose
.claude/skills/add-acp-server/SKILL.md	Install steps + IDE config (JetBrains, Zed, acpx)
.claude/skills/add-acp-server/scripts/claw-acp.ts	Bridge script (TypeScript/Bun, no build step)
.claude/skills/add-acp-server/scripts/claw-acp.test.ts	Test suite (23 tests, bun:test)

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Tests

23 tests, no live NanoClaw instance required. Mirrors the test structure of acp-client.test.ts using MockIO + MockCli helpers.

bun test ./.claude/skills/add-acp-server/scripts/claw-acp.test.ts

 23 pass
  0 fail
 44 expect() calls
Ran 23 tests across 1 file. [119.00ms]

Coverage:

Group	Tests
LineReader	feed/readLine, partial chunks, blank lines, end-of-stream, queued lines before null
handleInitialize	correct protocol fields, id echoed
handleSessionNew	valid UUID in result
handleSessionPrompt	happy path, empty prompt, 50ms timeout, CLI socket closed mid-wait, multi-block concat
handleSessionCancel / handleSessionClose	respond {}
handleFsReadTextFile	reads file, line/limit, path outside root, missing path, file not found
run() dispatch	unknown method → -32601, notification ignored, invalid JSON skipped

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Known limitations

• Single active session — CLI channel supports one client at a time; a second claw-acp process evicts the first
• Non-streaming — full response delivered as one session/update chunk, not token-by-token
• Read-only filesystem — fs/read_text_file supported; fs/write_text_file not
• Requires running NanoClaw — claw-acp is a bridge, not a standalone AI server