MCP integration

miucr mcp exposes the review engine to MCP clients over standard input/output, so a coding agent (Claude Code, Codex, …) can run reviews as a first-class tool instead of shelling out and parsing text.

Command

miucr mcp                       # stdio MCP server (default transport)
miucr mcp --transport stdio

The server reviews the repository in its current working directory, so launch it from (or point the host at) the repo you want reviewed.

Important

Stdout is reserved for MCP protocol frames. Startup errors, SDK logs, and diagnostics go to stderr, keeping the JSON-RPC stream clean.

The global --timeout flag applies to each call. Tool outputs are byte-bounded (default 1 MiB); an oversized result fails with review.output_too_large rather than flooding the host.

Tools

review_run

Review local git changes (staged, a range, or a single commit) and return gated findings, anchored to line numbers from the reviewed revision.

Argument	Type	Notes
staged	bool	Review staged changes against the index.
from	string	Range mode: base ref (use with to).
to	string	Range mode: target ref (use with from).
commit	string	Review a single commit against its parent.
gate	string	none|info|low|medium|high|critical. Defaults to high.
expand	int	Context lines above/below each hunk. Defaults to 5; 0 disables.
token_budget	int	Approximate token budget; over budget degrades context. 0 disables.

Select exactly one mode (staged, from+to, or commit) — the same validation as the CLI. Returns { id, findings, stats }; id is the persisted review id (use it with review_get).

review_get

Fetch a persisted review by id, as returned from a prior review_run.

Argument	Type	Notes
id	string	The review id returned by a prior review_run.

Returns { id, repo_dir, mode, head_sha, created_at, findings, stats }.

Host setup

Claude Code

Use the CLI:

claude mcp add --transport stdio miucr -- miucr mcp --transport stdio

Or add a project-scoped .mcp.json:

{
  "mcpServers": {
    "miucr": {
      "type": "stdio",
      "command": "miucr",
      "args": ["mcp", "--transport", "stdio"],
      "env": { "ANTHROPIC_API_KEY": "..." }
    }
  }
}

Reference: Claude Code MCP documentation.

Codex

Codex reads MCP server entries from ~/.codex/config.toml under mcp_servers.<id>:

[mcp_servers.miucr]
command = "miucr"
args = ["mcp", "--transport", "stdio"]
startup_timeout_sec = 10
tool_timeout_sec = 120

[mcp_servers.miucr.env]
ANTHROPIC_API_KEY = "..."

Reference: OpenAI Codex configuration reference.

Tip

The MCP server needs a provider key in its environment just like the CLI. Pass it through the host’s env block (above) or export it before the host launches miucr. See Credentials.

Troubleshooting

• If the host cannot start the server, use a full path from which miucr.
• If no tools appear, restart the host and check its MCP panel.
• If a review returns no findings, confirm the server’s working directory is the repo and that the selected mode actually has changes.
• If output fails with review.output_too_large, narrow the review (fewer files, a smaller range).