pr-council-mcp

Platform support: macOS only for now. Why Linux support is pending.

Illustrative, time-compressed replay with a fictional PR. Open the interactive version and transcript.

pr-council-mcp is a playground for agentic engineering end to end. It explores production concerns such as durable workflows, model coordination, sandboxed tools, secrets, human approval, and observability in a local environment with a small footprint: one stdio MCP server backed by SQLite, without a service stack to deploy.

The concrete application is multi-model review of GitHub pull requests. Independent quality and security reviewers inspect a PR, deliberate over their findings, and combine retained issues into a preview. The calling agent shows that preview to a human; only after explicit approval does the server publish inline comments and a COMMENT-only summary to GitHub.

Status: early development (alpha). The design, tool surface, and configuration are still changing and may break between versions. Expect rough edges, and expect the interfaces to evolve as both tracks are explored.

Quickstart

The server currently runs on macOS and requires Python 3.12+. Install uv, git, rg, and gh, then authenticate GitHub:

gh auth login
gh auth status

On first launch, the server creates ~/.config/localmcp/localmcp.toml (or the path beneath $XDG_CONFIG_HOME) with this base configuration if the file does not exist. The llm, secrets, and observability tables are owned by localmcplib; pr-council owns only its optional pr_review table:

schema_version = 1

[llm]
backend = "native"

[secrets.openai_api_key]
env_vars = ["OPENAI_API_KEY"]

[secrets.anthropic_api_key]
env_vars = ["ANTHROPIC_API_KEY"]

On macOS, store the keys in your default Keychain. Each command prompts for the key without putting it in shell history:

security add-generic-password -U -s localmcp -a openai_api_key -w
security add-generic-password -U -s localmcp -a anthropic_api_key -w

Only the providers used by your selected models need keys. macOS may ask you to allow the server to read these Keychain items. The server starts without keys and reports missing credentials when a review is requested.

Install the package on demand from public PyPI in your MCP client configuration.

Claude Code

Add .mcp.json:

{
  "mcpServers": {
    "pr-council-mcp": {
      "command": "uvx",
      "args": ["--from", "pr-council-mcp", "pr-council-mcp"]
    }
  }
}

opencode

Add opencode.jsonc:

{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "pr-council-mcp": {
      "type": "local",
      "command": ["uvx", "--from", "pr-council-mcp", "pr-council-mcp"]
    }
  }
}

How it works

Reviews are checkpointed operations rather than one long MCP request. The client starts a review, polls it, presents the exact revision-bound preview, and publishes only after explicit approval. Restarts can recover unfinished work, and publication revalidates the PR revision and approved payload before writing.

By default the server prepares an isolated managed worktree. Reviewer and deliberator models receive one bounded Bash tool inside a read-only macOS Seatbelt sandbox. They can inspect source and Git history with ordinary local tools, but cannot write files, access the network or credentials, or execute repository code. A local-checkout mode is also available when cloning a large repository is impractical.

The MCP surface intentionally stays small: start, status, preview, commit, and cancel. Published reviews contain inline comments plus a COMMENT-only summary; the server never approves or rejects a pull request.

Tools

Inspect the MCP server's tool schema for complete arguments and return models.

Basic configuration

Configuration lives at ~/.config/localmcp/localmcp.toml, or beneath $XDG_CONFIG_HOME when set. Shared root values are inherited by every local MCP server and [server.pr-council-mcp] overrides this server's application settings. Unknown application keys are rejected. The generated configuration uses the default reviewer matrix.

Secrets resolve from declared environment aliases first and the shared localmcp OS-keyring service second. The native backend resolves openai_api_key and anthropic_api_key as required by the selected models. GitHub authentication is owned by gh, with GH_TOKEN or GITHUB_TOKEN available as overrides. Secret values are never logged.

Structured logs are written only to ~/.local/state/localmcp/pr-council-mcp/logs/pr-council-mcp.log (or beneath $XDG_STATE_HOME) because stdout and stderr carry the MCP protocol. Langfuse tracing is optional and enabled with LOCALMCP_LANGFUSE_ENABLED=true. Tool inputs and outputs remain suppressed unless LOCALMCP_LANGFUSE_CAPTURE_PAYLOADS=true is also set.

License

Apache-2.0