API-existence Oracle: package
Deterministic package existence for PyPI and npm, built from real published artifacts (never LLM guesses). Negative answers and typosquat-adjacency flags carry signed proof. $0.002 USDC per check.
Go to this service →Our latest check (2026-10-11)
- Answering
- Yes — valid x402 payment terms
- Time to answer
- 10326 ms
- Price
- $0.002 per call
- Paying buyers, last 30 days
- 1 (directory's own records)
- Paid calls, last 30 days
- 1
- Category
- AI model answers
- Address
- https://attester.dev/v1/package/exists
Accuracy: paid answers checked against an independent record
Not yet in our paid checks. A seller we have not checked has neither passed nor failed.
For agents
This page as JSON: /sellers/c6ec73b139d9.json. Paid lookup by address: GET /api/seller?resource=… ($0.001, x402).