MCP PR Workflow Server

MCP server that connects AI assistants to GitHub PRs, CI, and Slack — with guardrails. Built in TypeScript for teams that want automated PR triage and deployment notifications without giving an LLM unbounded access to repos or chat.

At a glance

Related MCP server: Agentic MCP Server

What this demonstrates

• Integration design — Third-party APIs (GitHub, Slack) wrapped as a small, testable tool surface for LLM clients.

• Security-by-default — Repo allowlists, channel allowlists, input validation, prompt-injection checks, and secret redaction before anything leaves the process.

• Reliable server behavior — Unknown tools and validation failures return MCP errors (isError: true) instead of crashing the server.

• Separation of concerns — Tool registration, request dispatch, security, and resources live in focused modules with dedicated tests.

• MCP fluency — Tools, resources, and prompts implemented against the Model Context Protocol spec.

Architecture

flowchart LR
  Client[AI Client / Claude Desktop] -->|stdio MCP| Server[MCP Server]
  Server --> Dispatch[runtime.dispatchToolCall]
  Dispatch --> PR[PR Tools]
  Dispatch --> CI[CI Tools]
  Dispatch --> Slack[Slack Tools]
  Dispatch --> Issues[Issue Tools]
  PR --> GitHub[GitHub API]
  CI --> GitHub
  Issues --> GitHub
  Slack --> SlackAPI[Slack Web API]
  Dispatch --> Security[validation · allowlist · sanitize]
  Security --> Dispatch

Request flow: Client calls a tool → input is validated → repo/channel allowlists are enforced → external API runs → response is sanitized → result returned (or structured error).

Security model

Designed for least privilege when an LLM can trigger side effects:

Startup fails fast if required configuration is missing or invalid.

Tools & resources

Quick start

git clone <repo-url>
cd MCP-PR-Workflow-Server
npm install
cp .env.example .env   # fill in tokens and allowlists
npm test                 # 84 tests
npm run build
npm start

Environment

Retrieve GITHUB_TOKEN from https://github.com/settings/personal-access-tokens. Repository permissions: Read access to actions, code, and metadata Read and Write access to deployments, issues, and pull requests

GITHUB_TOKEN=github...
SLACK_BOT_TOKEN=xoxb-...
SLACK_CHANNEL_ID=C12345678
ALLOWED_REPOS=your-org/your-repo,another-org/another-repo

Claude Desktop

1. Open Claude Desktop and click your profile name or the menu to open Settings.

2. Go to the Developer tab and click Edit Config. This opens the claude_desktop_config.json file.

3. Add your MCP server details inside the mcpServers JSON object.

{
  "mcpServers": {
    "pr-workflow": {
      "command": "node",
      "args": ["/absolute/path/to/MCP-PR-Workflow-Server/dist/index.js"],
      "env": {
        "GITHUB_TOKEN": "your_github_token",
        "SLACK_BOT_TOKEN": "xoxb-your-token",
        "SLACK_CHANNEL_ID": "C12345678",
        "ALLOWED_REPOS": "your-org/your-repo"
      }
    }
  }
}

Project layout

src/
├── index.ts              # MCP server + handler registration
├── runtime.ts            # Startup checks + tool dispatch
├── tools/                # GitHub, CI, Slack, issue tools
├── resources/            # Team config resources
├── prompts/              # Workflow prompts
└── security/             # Validation, allowlists, sanitization