APIs evolve constantly. Endpoints get deprecated. Parameters change. Auth flows update. openapi.city tracks every change — version diffs, automated refreshes, always-current specs.
Stripe deprecated charges.create in favor of payment_intents.create. They didn't email you. Your integration kept calling the old endpoint. It worked for a while. Then it didn't. Your users found out first.
You integrate with Stripe, Slack, GitHub, Twilio, and Cloudflare. Each one updates their API regularly. Tracking changes across five providers manually is a part-time job. Miss one changelog email and you're behind.
Some providers publish detailed changelogs. Others don't. Some announce breaking changes months in advance. Others ship them on a Tuesday. There's no consistent way to know what changed, when, and whether it affects your integration.
2am pages. Angry users. Rushing a hotfix because a provider changed something you didn't know about.
Subscribing to 10+ developer blogs, parsing changelogs, diffing specs by hand. Hours per week.
"Why does the Slack integration keep breaking?" Users don't care that Slack changed their API. They care that your tool doesn't work.
We re-fetch specs from source every week. GitHub, Stripe, Slack — every provider gets checked. If the spec changed, we ingest the new version and compute a diff automatically.
Every version stores a machine-readable diff: added_endpoints, removed_endpoints, changed_endpoints with field-level detail. Query via REST or MCP.
If ingestion fails, the previous working version stays active. No broken integrations because our parser choked on a malformed spec. Errors are logged and retried.
Query any version diff via REST or MCP.
Structured, machine-readable spec data for any automation platform.
Weekly checks against your integrations. Know the day an API changes, not the day your users complain.
Full history of every spec change. Audit what changed and when. Plan migrations before they become emergencies.
No chasing references through nested files. Get complete, resolved schema definitions for validation and code generation.
Index APIs we haven't covered yet. POST a spec URL and get structured data in minutes, not hours.
No credit card required. Upgrade when your agents need more.
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Production AI agents
Stop finding out about API changes from angry users. Start tracking them programmatically.
