Type/shape diffing, not value diffing

Their API changed. Your app broke. Know first.

SchemaGuardian probes the third-party APIs you depend on and emails you when a response schema silently drifts — type changes, removed fields, shape breaks — before production notices.

No credit card required · 3 probes free forever

probe: GET /v1/balance (Stripe)
# schema diff — run #482
+ field "available[].currency" added (non-breaking)
- "pending[].amount" type changed number → string
Drift candidate 2/3 confirmations — watching

Prebuilt probe templates for

StripeRazorpayGitHubSlackOpenAIAnthropicTwilioSendGridHubSpotShopify

How it works

Watching the shape, not the noise

01

Register a probe

Point SchemaGuardian at an endpoint you depend on — pick a prebuilt recipe or add your own URL and credentials.

02

We fingerprint the schema every cycle

Every run infers the response's type/shape and hashes it — never the values, never your data.

03

Drift alert after 3 consecutive confirmations

A change has to repeat 3 runs in a row before we email you. No flapping fields, no false-positive noise.

Why it's different

Built to be quiet until it matters

Shape-level diffing

We diff schemas, not values.

A price changing from 999 to 1099 never alerts you. A field silently changing from a number to a string does. Value noise is filtered out by construction.

3-run stabilization

No 3am pages for a flaky field.

A drift candidate has to reappear on 3 consecutive probe runs before it becomes an alert. Transient API hiccups heal themselves and never reach your inbox.

AES-256-GCM at rest

Your API keys, encrypted — always.

Auth headers are encrypted before they touch the database and are never logged or returned by any query. We store schemas, never response bodies.

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Know before
production notices.

Set up a probe in 2 minutes. No credit card. 3 probes free forever.

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Drift alerts by email · No Slack/webhooks yet

SchemaGuardian — Their API changed. Your app broke. Know first.