PatchNote MCP — Live Dependency Changelog and Breaking Change Context Server for Cursor and Claude
Your AI coding assistant gives confident upgrade advice using documentation that was accurate six months ago. PatchNote is an MCP server that injects live changelogs, breaking change warnings, and migration guides for any npm or PyPI package directly into Claude and Cursor before they suggest an upgrade. Ship with fresh context, not stale hallucinations.
Difficulty
intermediate
Category
MCP & Integrations
Market Demand
High
Revenue Score
6/10
Platform
MCP Server
Vibe Code Friendly
No
Hackathon Score
🏆 7/10
What is it?
Claude and Cursor regularly recommend package upgrades using training data that predates the actual release. PatchNote solves this by running as a local MCP server that fetches live changelogs from npm registry, PyPI, and GitHub releases, parses breaking changes using Claude, and exposes them as structured tools and resources to any MCP-compatible host. When a developer asks 'should I upgrade react-query to v6?', Cursor can call PatchNote's check_breaking_changes tool and get a real-time summary instead of hallucinating one. The MCP server also exposes a list_pending_upgrades resource that scans the local package.json or requirements.txt and surfaces all packages with newer versions plus their risk tier. Buildable in one week using the MCP TypeScript SDK, npm registry API, and PyPI JSON API — all free and stable.
Why now?
The MCP ecosystem exploded in early 2026 with Cursor adding native MCP support and Claude Desktop expanding tool calling — there is no live dependency context server in the MCP directory yet and the Cursor community is actively requesting one.
- ▸check_breaking_changes MCP tool that fetches and parses live changelogs for any npm or PyPI package version pair
- ▸list_pending_upgrades MCP resource that scans package.json or requirements.txt and tiers packages by upgrade risk
- ▸migration_guide MCP tool that returns the official migration path for a major version bump
- ▸Slack webhook alert on new major releases detected in the developer's current stack
Target Audience
TypeScript and Python developers using Cursor or Claude Desktop — roughly 800,000 active Cursor users as of May 2026.
Example Use Case
A developer asks Cursor 'is it safe to upgrade prisma from 5.x to 6.x?' — Cursor calls PatchNote's check_breaking_changes tool, gets a parsed list of three breaking schema changes and a migration guide link, and warns the developer before they run npm install.
User Stories
- ▸As a TypeScript developer, I want Cursor to tell me the actual breaking changes in a package upgrade, so that I never blindly run npm install on a major version bump.
- ▸As a Python developer, I want to see all outdated packages in my requirements.txt ranked by upgrade risk, so that I prioritize safe upgrades first.
- ▸As a developer on a team, I want a Slack alert when a major version of a package in our stack is released, so that we plan migrations proactively.
Done When
- ✓check_breaking_changes: done when developer types 'what breaks if I upgrade prisma from 5 to 6' in Cursor and receives a structured list of breaking changes from the live npm changelog within 5 seconds.
- ✓list_pending_upgrades: done when Cursor calls the resource and returns a table of outdated packages with their current version, latest version, and risk tier (low/medium/high).
- ✓migration_guide: done when developer asks for the migration path and receives a direct link and summary from the official GitHub release notes.
- ✓MCP registration: done when the server appears in Cursor's MCP tools panel after adding one line to mcp.json config.
Is it worth building?
$9 one-time on GitHub Sponsors or Gumroad x 2,000 downloads = $18,000. Or $7/month x 500 active users = $3,500 MRR. Math assumes 2% conversion from 25,000 Cursor community Discord members.
Unit Economics
CAC: $0 via open-source GitHub distribution. LTV: $84 (12 months at $7/month). Payback: immediate. Gross margin: 95%.
Business Model
One-time purchase or freemium
Monetization Path
Free open-source core, $7/month Pro for unlimited package scans and Slack/email alerts on breaking releases in your stack.
Revenue Timeline
First dollar: week 1 via Gumroad one-time. $1k MRR: month 3 via Pro tier. $3k MRR: month 7.
Estimated Monthly Cost
Claude API: $20 for changelog parsing, Vercel for Pro billing page: $0 (serverless), GitHub API: free. Total: ~$20/month at launch.
Profit Potential
Side income to $3k–$5k MRR via Pro tier.
Scalability
Medium — expand to cargo (Rust), pub (Dart), and RubyGems. Add a hosted cloud mode for CI/CD pipelines.
Success Metrics
Week 1: 100 GitHub stars. Week 2: 500 installs. Month 1: 50 Pro subscribers at $7.
Launch & Validation Plan
Post a side-by-side screen recording in r/cursor showing Cursor hallucinating a changelog vs PatchNote giving accurate breaking changes — measure upvotes before building Pro tier.
Customer Acquisition Strategy
First customer: post demo video in Cursor Discord and r/cursor showing the hallucination-vs-accurate-context comparison and link to GitHub repo with a Gumroad Pro upgrade. Then: GitHub trending via star campaign, ProductHunt as a developer tool, MCP server directory submissions.
What's the competition?
Competition Level
Low
Similar Products
Renovate for automated PRs, Dependabot for version alerts, Snyk for security — none expose live changelog context to AI coding assistants via MCP.
Competitive Advantage
Renovate and Dependabot flag outdated packages but do not inject context into AI coding assistants. No existing MCP server targets live dependency changelogs specifically.
Regulatory Risks
Low regulatory risk. npm and PyPI APIs are public. GitHub Releases API requires attribution per ToS.
What's the roadmap?
Feature Roadmap
V1 (launch): npm and PyPI changelog tools, list_pending_upgrades resource, Cursor integration. V2 (month 2-3): Slack alerts for new major releases, cargo support. V3 (month 4+): CI/CD webhook mode, hosted cloud API for teams.
Milestone Plan
Phase 1 (Week 1): MCP server with all three tools working locally in Cursor, published to npm. Phase 2 (Week 2): Pro tier billing via Gumroad, demo video posted in Cursor Discord. Phase 3 (Month 2): 50 Pro subscribers, GitHub trending in TypeScript category.
How do you build it?
Tech Stack
MCP TypeScript SDK, npm registry API, PyPI JSON API, GitHub Releases API, Claude API for changelog parsing, Node.js — build with Cursor for all server logic.
Suggested Frameworks
MCP TypeScript SDK, Zod, Cheerio
Time to Ship
1 week
Required Skills
MCP SDK, TypeScript, Node.js, API integration, JSON parsing.
Resources
MCP TypeScript SDK docs, npm registry API docs, PyPI JSON API, GitHub Releases API docs, Anthropic Claude docs.
MVP Scope
src/index.ts (MCP server entry, tool and resource registration), src/tools/checkBreakingChanges.ts (npm and PyPI changelog fetcher and Claude parser), src/tools/listPendingUpgrades.ts (package.json and requirements.txt scanner), src/tools/migrationGuide.ts (GitHub release note fetcher), src/resources/stackSnapshot.ts (current stack version reader), src/lib/npmRegistry.ts (npm API client), src/lib/pypiRegistry.ts (PyPI API client), src/lib/claudeParser.ts (changelog summarizer), package.json, .env.example.
Core User Journey
Install MCP server -> configure in Cursor settings -> ask about package upgrade -> receive live accurate changelog context in Cursor response.
Architecture Pattern
Cursor calls MCP tool -> PatchNote fetches npm or PyPI changelog API -> Claude API parses breaking changes into structured JSON -> result returned as MCP tool response -> Cursor injects into context window.
Data Model
PackageQuery has one ChangelogResult. ChangelogResult has many BreakingChanges. StackSnapshot has many PackageVersions.
Integration Points
MCP TypeScript SDK for tool and resource registration, npm registry API for package metadata, PyPI JSON API for Python packages, GitHub Releases API for migration guides, Claude API for changelog parsing.
V1 Scope Boundaries
V1 excludes: CI/CD integration, Slack alerts, cargo and RubyGems support, hosted cloud mode, team accounts.
Success Definition
A developer installs PatchNote, asks Cursor about a package upgrade, receives accurate breaking change context from the live registry, and never gets a hallucinated changelog again.
Challenges
The hardest non-technical problem is discoverability — MCP servers live or die by whether they appear in Cursor's extension marketplace or get featured in AI dev Twitter threads. Post a demo video showing the broken Cursor response versus the PatchNote-corrected one.
Avoid These Pitfalls
Do not parse changelogs with regex — use Claude to extract structured breaking changes from free-form markdown. Do not require Claude API key from end users in v1 — bundle a free tier parsing layer. Discoverability is harder than building — budget 3x more time on distribution than on the MCP server itself.
Security Requirements
No user auth required for local MCP server. API keys for Claude stored in local .env only. No user data leaves the local machine in free tier.
Infrastructure Plan
Local MCP server distributed via npm CLI install. Pro tier billing page on Vercel. No database required for v1. Sentry optional for error logging in Pro mode.
Performance Targets
Tool call response under 3 seconds including Claude API parsing. Local server startup under 500ms. npm registry API cached for 1 hour per package to avoid rate limits.
Go-Live Checklist
- ☐MCP tool schemas validated with Zod.
- ☐All three tools tested in Cursor end-to-end.
- ☐npm package published and installable via npx.
- ☐Gumroad Pro upgrade page live.
- ☐Demo video recorded and posted.
- ☐README with one-command install published.
- ☐5 beta developers confirmed working install.
- ☐Rollback plan documented.
- ☐r/cursor and Cursor Discord launch post drafted.
First Run Experience
On first run after npm install: the MCP server starts with zero config and Cursor immediately shows three available tools in its MCP panel. Developer can call check_breaking_changes on any package without setting up any API keys — a bundled free parsing tier handles the first 50 calls.
How to build it, step by step
1. Define MCP tool schemas for check_breaking_changes, list_pending_upgrades, and migration_guide using Zod. 2. Build npm registry API client fetching changelog URLs from package metadata. 3. Build PyPI JSON API client fetching release notes per version. 4. Write Claude prompt that parses raw markdown changelogs into structured breaking change arrays. 5. Implement list_pending_upgrades by reading local package.json and querying npm for latest versions. 6. Register all tools and resources in MCP server index using MCP TypeScript SDK. 7. Test server locally in Cursor by adding to mcp.json config. 8. Build a minimal Gumroad or Stripe payment page for the Pro tier upgrade. 9. Write a demo script showing Cursor hallucination versus PatchNote-corrected response for recording. 10. Publish to npm as a CLI-installable MCP server and walk the full install-to-first-tool-call journey end-to-end.
Generated
May 25, 2026
Model
claude-sonnet-4-6
Disclaimer: Ideas on this site are AI-generated and may contain inaccuracies. Revenue estimates, market demand figures, and financial projections are illustrative assumptions only — not financial advice. Do your own research before making any business or investment decisions. Technology availability, pricing, and market conditions change rapidly; always verify details independently.