Keystone Opportunity API
Deterministically score a task brief for deliverables, acceptance criteria, deadlines, constraints, and usable scope before committing time. No AI calls; same brief always yields the same score.
Go to this service →Our latest check (2026-10-11)
- Answering
- Yes — valid x402 payment terms
- Time to answer
- 473 ms
- Price
- $0.001 per call
- Paying buyers, last 30 days
- 3 (directory's own records)
- Paid calls, last 30 days
- 3
- Category
- Email and phone validation
- Address
- https://keystone-opportunity-api.keystone-opportunity.workers.dev/v1/brief-check
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/3787b3712aa3.json. Paid lookup by address: GET /api/seller?resource=… ($0.001, x402).