{"data":{"status":"fail","threshold":4.5,"results":[{"foreground":"#767676","background":"#ffffff","ratio":4.542224959605253,"ratioText":"4.54:1","meets":true},{"label":"caption","foreground":"#777777","background":"#ffffff","ratio":4.478089453577214,"ratioText":"4.47:1","meets":false,"fix":{"status":"found","target":"foreground","hex":"#777676","ratio":4.528436450868204,"ratioText":"4.52:1","direction":"darker","deltaL":-0.0017123862431300818,"gamutClipped":false,"oklch":{"L":0.5667122815511634,"C":0.0012236488869811321,"h":0.3001046241812216}}}],"witnesses":[{"ruleId":"wcag-contrast","detail":"contrast 4.47:1 is below 4.5:1","path":"pairs.1","index":1,"expected":4.5,"actual":4.478089453577214}],"versions":{"engine":"contrast-fix 1","wcag":"WCAG 2.2 W3C Recommendation 2024-12-12, relative luminance and contrast ratio definitions (sRGB threshold 0.04045), https://www.w3.org/TR/WCAG22/, fetched 2026-11-04","oklab":"Oklab matrices of 2021-01-25, https://bottosson.github.io/posts/oklab/, fetched 2026-11-04","cvd":"Machado, Oliveira, Fernandes 2009 IEEE TVCG 15(6) Table 1 simulation matrices (linear RGB), https://www.inf.ufrgs.br/~oliveira/pubs_files/CVD_Simulation/CVD_Simulation.html, fetched 2026-11-04","fixSearch":"bisection on OKLCH L only, 40 iterations, channel clipping, 8-bit quantisation"},"limits":["The fix is minimal along lightness at fixed chroma and hue and assumes the pass region is contiguous; it is not the globally nearest colour. Clipping can shift hue (gamutClipped says so)."],"deterministic":true},"_provenance":{"version":"writerslogic-provenance/1","issuer":"did:web:agents.writerslogic.com","verify":{"endpoint":"POST /api/v1/verify-provenance","did":"did:web:agents.writerslogic.com"},"manifest":{"format":"application/json","instance_id":"xmp:iid:b8b65b1e-bb4f-4513-930d-20e91b95973b","claim_generator_info":[{"name":"WritersLogic x402 Agent Hub","version":"2.0.0"}],"title":"WCAG 2.2 contrast check with the minimal OKLCH lightness fix and colour-blind pair check","assertions":[{"label":"c2pa.actions.v2","data":{"actions":[{"action":"c2pa.created","when":"2026-11-06T01:30:31.464Z","softwareAgent":{"name":"writerslogic-agent-hub/contrast-fix","version":"2.0.0"},"digitalSourceType":"http://cv.iptc.org/newscodes/digitalsourcetype/algorithmicMedia","parameters":{"endpoint":"POST /api/v1/contrast-fix","inputDigest":{"alg":"sha256","hash":"30f5e208f532ebb7463649129789a37c0b3c856efb0b679862052164ce5eba0a","canonicalization":"JCS"}}}]}},{"label":"c2pa.hash.data","data":{"alg":"sha256","hash":"1df6ee35e843b2da6780ad436d01ae116f64ad7e5154e235dca97ee7575c842e","name":"jcs-canonical-json(data)"}}]},"credential":{"@context":["https://www.w3.org/ns/credentials/v2"],"id":"urn:uuid:4f912970-5f89-4a6a-a34d-43fad092d7f6","type":["VerifiableCredential","AgentOutputCredential"],"issuer":"did:web:agents.writerslogic.com","validFrom":"2026-11-06T01:30:31.464Z","credentialSubject":{"id":"urn:sha256:1df6ee35e843b2da6780ad436d01ae116f64ad7e5154e235dca97ee7575c842e","agent":"contrast-fix","endpoint":"POST /api/v1/contrast-fix","outputDigest":{"alg":"sha256","value":"1df6ee35e843b2da6780ad436d01ae116f64ad7e5154e235dca97ee7575c842e","canonicalization":"JCS"},"inputDigest":{"alg":"sha256","value":"30f5e208f532ebb7463649129789a37c0b3c856efb0b679862052164ce5eba0a","canonicalization":"JCS"},"manifestDigest":{"alg":"sha256","value":"566493ee0d1d36ee249e15688b798bc73c1aac97616e2a51377821089c9cfd09","canonicalization":"JCS"},"ingredients":[],"payment":{"scheme":"api-key","network":"eip155:8453","payer":"sample"}},"proof":{"type":"DataIntegrityProof","cryptosuite":"eddsa-jcs-2022","created":"2026-11-06T01:30:31.464Z","verificationMethod":"did:web:agents.writerslogic.com#key-1","proofPurpose":"assertionMethod","proofValue":"z4LHZGgc3W9pZHK3DgXs476b98ddvidCgZadp99XsVKDnBcSZ1FBST94LS6wYG6r6XNKc51Q14ezh8Jza3Jm5E8mD"}},"ethSignature":{"type":"EIP-191","signer":"did:pkh:eip155:8453:0x3DBd42560cA7a7E448A2c7DfC9E785526189411f","address":"0x3DBd42560cA7a7E448A2c7DfC9E785526189411f","message":"writerslogic-provenance:9b8745f35bad210e7eab76e3848ec5820deed0c5a549b2a14da854d8895f65b4","signature":"0x8c508104f56e0837b525efbfb6d0843dbe2dc0a585fc2875ba9ec0a24c81fd2c46c3ee11a383cf7a6b388af39bc6823a1e74c5a1a3fbc7f44b7488ca47e1fa441b"}}}