{"uid":"cap_iWm3QEJ8IfuqLE9MeYbrw","slug":"keystone-opportunity-api-brief-check-51f2db5a","name":"Keystone Opportunity API – Brief Check","description":"Low-cost, deterministic x402 utilities for autonomous agents on Base. Every /v1 route is priced in USDC and settles onchain via the x402 protocol; discover and pay programmatically through the x402 Bazaar. No API keys, no subscriptions.","url":"https://keystone-opportunity-api.keystone-opportunity.workers.dev/v1/brief-check","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"brief":{"type":"string","maxLength":8000,"minLength":1,"description":"Task brief to validate."}}},"responseSchema":{"type":"json","example":{"ready":false,"score":80,"checks":[{"id":"deliverable","passed":true,"message":"Name the exact file, artifact, or outcome to deliver."}],"characters":121}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_SemTGR0Ya29252VBMJWNc","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Validates a task brief for autonomous agents, scoring it for completeness and readiness before execution","exampleAgentPrompt":"Before I kick off this job, can you check if my task brief is ready? Here it is: 'Generate a 500-word blog post about EV adoption trends and save it as blog-post.md in the /output folder.'","exampleUseCases":[{"title":"Pre-flight check before agent execution","prompt":"I want to make sure my brief is solid before my agent starts working on it — can you validate this: 'Scrape the top 10 products from example.com/shop and export the names, prices, and URLs as a CSV file named products.csv'?"},{"title":"Debugging a low-quality task spec","prompt":"My agent keeps failing on this task and I think the brief might be the problem. Can you score this brief and tell me what's wrong with it: 'Look into the competitor landscape and write something useful about it'?"},{"title":"Iterating on a prompt before deployment","prompt":"I'm building an automated workflow and want to make sure the task brief I'm feeding it will pass validation — check this one for me: 'Summarize the attached PDF report into 3 bullet points and email them to the team lead by 5pm every Friday.'"}],"resultDescription":"Returns a JSON object with a boolean 'ready' flag, an integer 'score' (0-100), an array of 'checks' each with an id, passed status, and descriptive message, and a 'characters' count of the brief. Agents can use the score and failed checks to iteratively improve the brief before execution.","failureModes":["Brief text is empty or missing — returns 400 with validation error","Brief exceeds 8000 character limit — returns 400 with length error","Payment not included or insufficient USDC — returns 402 challenge via x402 protocol","Malformed JSON body — returns 400 parse error"],"whenToPreferThis":"Choose this endpoint when you need a deterministic, low-cost check on a task brief before handing it off to an autonomous agent. Ideal for agentic pipelines that want to catch ambiguous or incomplete instructions early, reducing downstream failures. At $0.001 USDC per call it is cheap enough to run on every brief in a workflow. Prefer this over manual review or LLM self-assessment when you need a consistent, structured scoring rubric with specific named checks.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T00:31:55.210Z","isFirstParty":false}