REST & MCP · contract monitoring

Your API changed.
Nobody told you.

ContractWatch snapshots your REST or MCP contracts on a schedule and diffs them against yesterday. When something breaking slips in, you hear about it in Slack — before your users file the ticket.

Aug 4No changes
Aug 5No changes
Aug 6 · POST /v1/chargesBreaking change
− "customer_id": string (required)
+ "payment_method": string (required)

Any client still sending customer_id alone will start receiving 400s.

Breaking, warning, or info
Every change classified automatically, not just flagged.
Runs on your schedule
Daily up to every 15 minutes, depending on plan.
One failure won’t block another
Every monitor checks independently.

Built for the moment things drift

REST & MCP, one tool

Point it at an OpenAPI spec or an MCP server. Same diff engine, same alerts.

Real diffs, not status codes

See the exact field, type, or tool signature that changed — not just “something broke.”

Alerts where you work

Slack, email, or a webhook into your own system. No dashboard you have to remember to check.

Free to start

2 monitors, daily checks, email alerts — no credit card required. Upgrade when you outgrow it.

Pricing

Free

$0
  • 2 monitors
  • Daily checks
  • Email alerts
Get started

Developer

$19/mo
  • 10 monitors
  • Hourly checks
  • Slack + email alerts
Get started

Team

$49/mo
  • Unlimited monitors
  • 15-min checks
  • Slack + email + webhook alerts
Get started