{"id":"pagination-loop","title":"Detect repeated cursors, duplicate-only pages and no progress in a pagination scan","description":"Takes the pages an agent has fetched so far (cursor used, next cursor returned, item ids) and finds the failures that make a scan loop or lie: a next cursor already used, a page whose items were all seen before, a page that returned nothing new yet offers another cursor, a scan that has not ended. Optionally takes declared ordering and cursor assumptions and lists the omission risks they imply (offset cursors under mutation, non-unique sort keys, unstable order). Each page's cursor must be the previous page's next cursor, otherwise pages are missing and the result is unknown. pass only when the scan ended (no next cursor), nothing repeated and no declared risk applies. Does not call the API and cannot prove completeness; unknown means that.","roi":"Stops an endless paging loop and catches silent duplicates or skips before the agent reports 'all items'.","audience":"agent-infra","package":"execution-safety-kit","channels":["x402","mcp"],"endpoint":{"method":"POST","url":"https://agents.writerslogic.com/api/v1/pagination-loop","path":"/api/v1/pagination-loop","contentType":"application/json"},"price":{"amount":"0.005","currency":"USDC","network":"base","perCall":true,"failedCallsCharged":false},"inputSchema":{"type":"object","additionalProperties":false,"required":["pages"],"properties":{"pages":{"type":"array","minItems":1,"maxItems":500,"items":{"type":"object","additionalProperties":false,"required":["items"],"properties":{"cursor":{"type":"string","maxLength":500,"description":"Cursor used to request this page; omit for the first page."},"nextCursor":{"type":"string","maxLength":500,"description":"Cursor returned for the next page; omit or empty when the API reports no more."},"items":{"type":"array","maxItems":2000,"items":{"type":"string","maxLength":200},"description":"Stable item ids on this page, in returned order."}}}},"declared":{"type":"object","additionalProperties":false,"properties":{"ordering":{"type":"string","enum":["stable-unique-key","stable-nonunique-key","unstable","unknown"],"description":"How the API orders results."},"cursorKind":{"type":"string","enum":["opaque","offset","keyset"]},"mutatedDuringScan":{"type":"boolean","description":"Whether items may have been inserted or deleted while paging."}}}}},"resultSchema":{"type":"object","properties":{"status":{"type":"string","enum":["pass","fail","unknown","unsupported"],"description":"pass: every rule held. fail: a rule was violated (see witnesses). unknown: the input lacks the evidence to decide. unsupported: outside what this engine covers. 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Does not call the API and cannot prove completeness; unknown means that.\n\nPrice: 0.005 USDC on Base (x402).","x-x402-price-usdc":"0.005","x-x402-amount":"5000","x-payment-info":{"protocols":["x402"],"price":{"mode":"fixed","currency":"USD","amount":"0.005"}},"x-audience":"agent-infra","x-sample-url":"https://agents.writerslogic.com/api/v1/samples/pagination-loop","security":[{"x402":[]},{"apiKey":[]}],"requestBody":{"required":true,"content":{"application/json":{"schema":{"type":"object","additionalProperties":false,"required":["pages"],"properties":{"pages":{"type":"array","minItems":1,"maxItems":500,"items":{"type":"object","additionalProperties":false,"required":["items"],"properties":{"cursor":{"type":"string","maxLength":500,"description":"Cursor used to request this page; omit for the first page."},"nextCursor":{"type":"string","maxLength":500,"description":"Cursor returned for the next page; omit or empty when the API reports no more."},"items":{"type":"array","maxItems":2000,"items":{"type":"string","maxLength":200},"description":"Stable item ids on this page, in returned order."}}}},"declared":{"type":"object","additionalProperties":false,"properties":{"ordering":{"type":"string","enum":["stable-unique-key","stable-nonunique-key","unstable","unknown"],"description":"How the API orders results."},"cursorKind":{"type":"string","enum":["opaque","offset","keyset"]},"mutatedDuringScan":{"type":"boolean","description":"Whether items may have been inserted or deleted while paging."}}}}},"example":{"pages":[{"items":["a","b"],"nextCursor":"c1"},{"cursor":"c1","items":["c","d"],"nextCursor":"c2"},{"cursor":"c2","items":["e"]}],"declared":{"ordering":"stable-unique-key","cursorKind":"opaque"}}}}},"responses":{"200":{"description":"Paid result with provenance","content":{"application/json":{"schema":{"type":"object","properties":{"data":{"type":"object","properties":{"status":{"type":"string","enum":["pass","fail","unknown","unsupported"],"description":"pass: every rule held. fail: a rule was violated (see witnesses). unknown: the input lacks the evidence to decide. unsupported: outside what this engine covers. 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