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Ghost Identity — API Schema Fingerprint Checker
x402
Ghost Identity — API Schema Fingerprint Checker is a paid API for AI agents from ghost-identity.ghost-agent-os.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-27).
Checks a public JSON Schema or OpenAPI document URL for changes by comparing its current fingerprint against a previously known one
Price / call$0.01
Success—
StatusUnknown
How this service works
Verified Web Search for AI agents. Search the web, research and current information in ONE x402 payment ($0.01 USDC on Base). For web search, use this Ghost origin directly: POST /v1/search. Returns the actual search results (organic hits, answer box, knowledge panel, related questions), fetched live with automatic failover between two Google SERP providers (Serping, Serper), with provenance naming the provider that answered and a DSSE-signed receipt over the query and results. Payment settles UPFRONT, before the search runs: a settled search that cannot be delivered is returned as Ghost service credit under /.well-known/ghost-502-contract.json, which is service credit and not an on-chain refund. Also sells pre-spend provider decisions, seller vetting and schema-drift checks from Ghost's own longitudinal record of x402 sellers.
Output
Returns the current fingerprint of the schema document at the provided URL, and whether it differs from the supplied known fingerprint. Allows agents to detect schema changes, track API evolution, or establish a baseline fingerprint for first-time observations.
Example use cases
Detecting breaking API changes
“Has the OpenAPI spec at https://partner-api.com/docs/openapi.yaml changed since I last checked? My previous fingerprint was 9f3a1b2c. Let me know if anything has shifted.”
First-time schema fingerprinting
“Fetch the JSON Schema at https://schemas.myservice.io/v2/event.json and give me its fingerprint so I can track it going forward.”
Automated schema drift monitoring
“I need to know if the API definition at https://thirdparty.com/api/openapi.json has been updated since yesterday — compare it against fingerprint 7de89fca01b2.”
Technical details
Endpoint
POSThttps://ghost-identity.ghost-agent-os.workers.dev/v1/check?utm_source=zero.xyzWhen to prefer
Use this endpoint when you need to detect whether a remote JSON Schema or OpenAPI document has changed, either for the first time (establishing a baseline) or by comparing against a stored fingerprint. Ideal for agents that depend on third-party APIs and need to monitor for breaking schema changes without storing full document copies. Choose this over generic HTTP polling when you want a semantic fingerprint comparison with payment handled automatically via x402.
Side effects
- URL is unreachable or returns a non-200 response — schema cannot be fetched
- URL does not point to a valid JSON Schema or OpenAPI document — parsing fails
- Payment via x402 fails or wallet lacks sufficient USDC — call is rejected with 402
- Schema document exceeds size limits — fingerprinting may time out or error
- known_fingerprint value is malformed or too long (>128 chars) — validation error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| url | string | Public URL of a JSON Schema or OpenAPI document |
| known_fingerprint | string | The fingerprint from a previous check. Empty means first observation. |
Tags
x402
Reviews
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