not-ace-tool-rs

An MCP server that gives AI coding agents grounded codebase context, prompt enhancement, web search, and mid-task advice from a Finnian/ACE backend.

Your editor launches this binary as a subprocess. It speaks JSON-RPC 2.0 over stdio and proxies tool calls to your Finnian/ACE server, so the agent answers from a real index of your codebase instead of guessing.

Quick Start

npx not-ace-tool-rs --base-url <API_URL> --token <AUTH_TOKEN>

npx downloads the right platform package, starts the server, and serves MCP tools over stdio. Supports Linux (x64/ARM64), macOS (x64/ARM64), and Windows (x64/ARM64).

Tools

| Tool | What it does | |---|---| | codebase_retrieval | Retrieve ranked code context for a natural-language question, scoped to indexed blobs | | enhance_prompt | Rewrite a prompt using retrieved codebase context | | web_search | Search the web through the server | | advisor | Ask for a course correction mid-task: assessment, recommendation, and the failure mode to watch for |

advisor requires a server exposing POST /agents/advisor. Against an older backend it returns a clear "not supported" result instead of failing the session, so one binary works across server versions.

MCP Client Setup

Claude Code

claude mcp add-json not-ace-tool --scope user '{
  "type": "stdio",
  "command": "npx",
  "args": ["not-ace-tool-rs", "--base-url", "https://your-api.example.com", "--token", "your-token"]
}'

Then allow the tools in ~/.claude/settings.json:

{
  "permissions": {
    "allow": [
      "mcp__not-ace-tool__codebase_retrieval",
      "mcp__not-ace-tool__enhance_prompt",
      "mcp__not-ace-tool__web_search",
      "mcp__not-ace-tool__advisor"
    ]
  }
}

Claude Desktop

~/Library/Application Support/Claude/claude_desktop_config.json on macOS:

{
  "mcpServers": {
    "not-ace-tool": {
      "command": "npx",
      "args": ["not-ace-tool-rs", "--base-url", "https://your-api.example.com", "--token", "your-token"]
    }
  }
}

Codex CLI

~/.codex/config.toml:

[mcp_servers.not-ace-tool]
command = "npx"
args = ["not-ace-tool-rs", "--base-url", "https://your-api.example.com", "--token", "your-token"]
startup_timeout_ms = 60000

Configuration

| Flag | Environment variable | Required | |---|---|---| | --base-url | FINNIAN_BASE_URL | Yes | | --token | FINNIAN_API_TOKEN | Yes |

Flags take precedence over environment variables. The base URL must be HTTP(S); trailing slashes are stripped. Startup fails with a message on stderr if either is missing.

Tool Reference

codebase_retrieval

| Parameter | Type | Required | Description | |---|---|---|---| | information_request | string | Yes | What you want to know, in natural language | | blobs | object | Yes | Blob scope: checkpoint_id, added_blobs, deleted_blobs | | max_output_length | integer | No | Cap on returned characters |

enhance_prompt

| Parameter | Type | Required | Description | |---|---|---|---| | prompt | string | Yes | The prompt to rewrite | | conversation_history | any | No | Prior turns, for continuity | | blobs | object | No | Blob scope to ground the rewrite |

web_search

| Parameter | Type | Required | Description | |---|---|---|---| | query | string | Yes | Search query | | count | integer | No | Results to return (the server caps this) |

advisor

| Parameter | Type | Required | Description | |---|---|---|---| | situation | string | Yes | The decision you face | | proposed_approach | string | No | What you are about to do; also sharpens retrieval | | transcript | string | No | Recent turns; tail-truncated when long | | blobs | object | No | Blob scope. Omit it and the advice is ungrounded — the response says so via grounded_in_code |

Notes

• stdout carries only JSON-RPC frames; all diagnostics go to stderr, so the protocol stays clean.
• Requests time out after 30 seconds.
• Upstream error bodies are truncated and stripped of the auth token before being surfaced, since MCP errors surface in your editor.

Building from Source

cargo build --release
./target/release/not-ace-tool-rs --base-url <API_URL> --token <AUTH_TOKEN>

License

GPL-3.0-only OR LicenseRef-Commercial. See LICENSE and LICENSE-COMMERCIAL.