Pr Narrator

npm version CI License: MIT

Generate consistent commit messages, PR content, and release notes automatically.

An MCP server that generates commit messages, PR content (titles, descriptions, and templates), and release notes from your git changes. If your repo doesn't already have a PR template, it auto-detects the domain (mobile, frontend, backend, devops, security, ML) and applies the right one — no config needed.

Install

npx pr-narrator-mcp

Quick Start

Cursor

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "pr-narrator": {
      "command": "npx",
      "args": ["-y", "pr-narrator-mcp"],
      "env": {
        "BASE_BRANCH": "develop",
        "TICKET_PATTERN": "[A-Z]+-\\d+"
      }
    }
  }
}

Claude Desktop

Add to your Claude Desktop config:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "pr-narrator": {
      "command": "npx",
      "args": ["-y", "pr-narrator-mcp"],
      "env": {
        "BASE_BRANCH": "develop",
        "TICKET_PATTERN": "[A-Z]+-\\d+"
      }
    }
  }
}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "pr-narrator": {
      "command": "npx",
      "args": ["-y", "pr-narrator-mcp"],
      "env": {
        "BASE_BRANCH": "develop",
        "TICKET_PATTERN": "[A-Z]+-\\d+"
      }
    }
  }
}

VS Code (GitHub Copilot)

Add to .vscode/mcp.json in your project:

{
  "servers": {
    "pr-narrator": {
      "command": "npx",
      "args": ["-y", "pr-narrator-mcp"],
      "env": {
        "BASE_BRANCH": "develop",
        "TICKET_PATTERN": "[A-Z]+-\\d+"
      }
    }
  }
}

Other MCP Clients

Any MCP client that supports stdio transport can use this server. The command is:

npx -y pr-narrator-mcp

That's it! No config files needed. All env vars are optional.

Settings

All settings are optional env vars in MCP JSON:

Env Var	What it does	Example
BASE_BRANCH	Base branch for PRs	develop
TICKET_PATTERN	Ticket regex	[A-Z]+-\\d+
TICKET_LINK	Ticket URL template	https://jira.example.com/browse/{ticket}
PREFIX_STYLE	Prefix format	capitalized or bracketed
DEFAULT_REPO_PATH	Fallback repo path (single-repo workflows)	/Users/me/my-project
PR_TEMPLATE_PRESET	Force a PR template preset	mobile, backend, devops
PR_DETECT_REPO_TEMPLATE	Enable/disable repo template detection	true (default) or false

If BASE_BRANCH is not set, it auto-detects from the repo (main, master, develop).

Note on repoPath: All tools accept a repoPath parameter. The AI calling the tool should pass the user's current workspace directory. DEFAULT_REPO_PATH is only a fallback for single-repo workflows.

Tools

PR Generation

generate_pr

Generate a complete PR with title, description, and context for AI enhancement. Automatically resolves the best template for the repo (see PR Templates).

Returns:

• title — PR title (placeholder derived from branch/commits — AI should rewrite)
• description — PR description with sections from the resolved template
• purposeContext — ALL commit titles, ALL commit bullets, test info, file count
• purposeGuidelines — Instructions for AI to rewrite title and Purpose from ALL data

Important: Both the title and Purpose are placeholders. The AI must read ALL purposeContext.commitTitles and purposeContext.commitBullets to synthesize a title and description that reflects the full scope of changes.

Optional templatePreset parameter to force a specific template (e.g., mobile, backend).

generate_pr_title

Generate a PR title based on branch info and commits.

generate_pr_description

Generate a PR description with auto-populated sections. Same template resolution as generate_pr but returns only the description. Accepts optional templatePreset and summary parameters.

get_pr_template

Preview the resolved PR template for a repo before generating. Shows which sections will appear based on the repo's template file, domain auto-detection, or configured preset. Useful for understanding what a PR will look like before calling generate_pr.

Returns the template source (repo, preset, auto-detected, or default), detected domain, and each section's visibility based on current branch changes.

Commit Messages

generate_commit_message

Prepare commit message context from staged or unstaged changes.

If nothing is staged, the tool automatically falls back to unstaged working tree changes and provides staging instructions — no need to run git add first just to analyze your changes. The response includes a source field ("staged" or "unstaged") and a hint with the exact git add command to run.

When includeBody is true, the actual diff is provided so the AI can write a meaningful body that describes what changed functionally — not just file type counts.

Two modes:

• With summary param (recommended): Returns a ready-to-use commit message with proper prefix/formatting. Add includeBody: true to get diff-based body generation.
• Without summary: Returns placeholder title + diff + guidelines for AI to compose the message and body

validate_commit_message

Check a commit message against configured rules (length, format, capitalization, imperative mood).

Release Notes

generate_changelog

Generate a changelog / release notes from git commit history between two refs (tags, SHAs, or branches).

• Auto-resolves refs — defaults from to the latest tag (or initial commit if no tags) and to to HEAD
• Parses commits — detects conventional commit types/scopes, infers types from keywords for non-conventional messages, extracts co-authors and ticket references
• Deduplicates squash-merge artifacts
• Three output formats: keepachangelog (default), github-release, plain
• Three grouping modes: type (default), scope, ticket
• Includes stats — commit count, contributor count, ticket count, and a one-line summary

Returns changelog (formatted markdown), entries (structured data), summary, stats, range, and warnings.

Repository Analysis

analyze_git_changes

Analyze the current repository state: staged changes, branch info, working tree status, and file categorization.

extract_tickets

Find ticket numbers in the branch name and commit messages using the configured TICKET_PATTERN.

get_config

See current settings and their resolved values.

Prefix Examples

Branch	Commit/PR Prefix
feature/PROJ-123-add-login	PROJ-123:
task/update-readme	Task:
bug/fix-crash	Bug:
main	(no prefix)

PR Templates

PR Narrator automatically selects the best template for each repository through a resolution pipeline:

1. Repo template — if a PULL_REQUEST_TEMPLATE.md exists in the repo (.github/, root, or docs/), it's parsed into sections
2. Explicit preset — if PR_TEMPLATE_PRESET is set or templatePreset is passed to a tool
3. Auto-detected domain — the repo's file tree is scanned and scored to detect its domain
4. Default — a universal 6-section template

This means switching between repos (iOS app, Express API, Terraform infra) automatically uses the right template with zero configuration.

Domain Auto-Detection

PR Narrator scans the top 3 levels of the repo file tree and scores files against domain signal patterns. The domain with the highest score wins, as long as it reaches a minimum threshold.

Domain	Key Signals	Sections Added
mobile	.swift, .kt, .xcodeproj, AndroidManifest.xml	Screenshots, Device Testing, Accessibility
frontend	.tsx, .vue, next.config, vite.config	Screenshots / Visual Changes, Browser Compatibility, Accessibility
backend	.go, .rs, migrations/, prisma/schema	API Changes, Database / Migration, Breaking Changes
devops	.tf, helm/, k8s/, Dockerfile	Infrastructure Impact, Affected Environments, Rollback Plan
security	.snyk, tfsec, trivy	Security Impact, Threat Model Changes
ml	.ipynb, model/, training/, dvc.yaml	Model Changes, Dataset Changes, Metrics / Evaluation

Available Presets

Preset	Sections	Best For
default	6	General-purpose repos
minimal	2	Quick PRs (Purpose + Test Plan)
detailed	10	Thorough reviews with screenshots, breaking changes, deployment notes
mobile	8	iOS and Android apps
frontend	8	Web apps (React, Vue, Svelte, etc.)
backend	8	APIs and services
devops	8	Infrastructure and CI/CD
security	7	Security-focused changes
ml	8	Machine learning and data science

Conditional Sections

Sections can appear or hide based on context:

• has_tickets — Ticket section only appears when tickets are found in the branch name or commits
• file_pattern — Screenshots section only appears when UI files are changed; Database section only when migration files are changed
• commit_count_gt — Changes (commit list) section only appears when there's more than 1 commit

Repo Template Detection

If your repo has a PULL_REQUEST_TEMPLATE.md, PR Narrator will find and parse it automatically. Supported locations:

• .github/pull_request_template.md
• .github/PULL_REQUEST_TEMPLATE/ (picks default.md first)
• pull_request_template.md (repo root)
• docs/pull_request_template.md

File names are matched case-insensitively. Both .md and .txt extensions are supported.

Set PR_DETECT_REPO_TEMPLATE=false to skip repo template detection and use presets or auto-detection instead.

Security

This MCP server is read-only and local-only (stdio transport). It never modifies your git repository, makes network requests, or handles authentication tokens.

Things to be aware of:

• Diffs may contain secrets. Staged changes and branch diffs are sent to the AI for analysis. If your commits contain API keys or passwords, these will be visible to the model. Use git-secrets or gitleaks to prevent committing sensitive data.
• Commit messages are untrusted input. Git commit messages from collaborators are passed to the AI. Adversarial commit messages could theoretically attempt prompt injection. The read-only nature of this MCP limits impact.
• Regex patterns are validated. The TICKET_PATTERN env var is checked for ReDoS safety (catastrophic backtracking, length limits) before use.

For full details, see SECURITY.md.

Development

git clone https://github.com/mhaviv/pr-narrator-mcp.git
cd pr-narrator-mcp
npm install
npm run build
npm test

License

MIT