{"uid":"cap_dYNftf2CN8ianvEF9poxB","slug":"agentrxi-image-diff-visual-regression-d57cf9c4","name":"AgentRXI Image Diff (Visual Regression)","description":"Compare two images pixel by pixel (visual regression testing for screenshots): count and percent of differing pixels with a fuzz tolerance, plus a diff image with the changes highlighted in red. Also callable as GET with the same fields as query parameters.","url":"https://agentrxi.com/v1/image/diff?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{"fuzz":{"type":"number","description":"Colour tolerance percent, default 3"},"store":{"type":"boolean","description":"Return 7-day share links instead of base64 (+$0.001); automatic above 3 MB"},"url_a":{"type":"string"},"url_b":{"type":"string"},"format":{"type":"string","description":"binary = raw file bytes (single output)"},"a_base64":{"type":"string"},"b_base64":{"type":"string"},"no_image":{"type":"boolean"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_RLUZRorOE6RQIqd2vXyIB","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Compares two images pixel by pixel, returning a count and percentage of differing pixels with configurable fuzz tolerance, plus a highlighted diff image showing changes in red.","exampleAgentPrompt":"Compare these two screenshots pixel by pixel and tell me how many pixels changed and what percentage — use a fuzz tolerance of 5% and highlight the differences in red: https://example.com/before.png and https://example.com/after.png","exampleUseCases":[{"title":"UI regression check after deployment","prompt":"I just deployed a frontend update — can you compare this before screenshot https://myapp.com/screens/before.png with this after screenshot https://myapp.com/screens/after.png using a 3% color fuzz tolerance and show me a diff image highlighting exactly what changed?"},{"title":"Design mockup comparison for QA","prompt":"My designer sent two versions of the same mockup — compare https://designs.io/v1.png and https://designs.io/v2.png pixel by pixel and tell me what percent of the image changed, with a fuzz of 2% to ignore compression artifacts."},{"title":"Monitor website visual changes","prompt":"Check if our homepage looks the same as it did yesterday — diff https://mysite.com/snapshots/yesterday.png against https://mysite.com/snapshots/today.png and give me the diff image as a shareable link so I can send it to the team."}],"resultDescription":"Returns a JSON object containing the count of differing pixels, the percentage of the image that differs, and a base64-encoded diff image (or a 7-day shareable link if store=true or the payload exceeds 3MB) with changed regions highlighted in red. The fuzz tolerance applied is also reported.","failureModes":["Invalid or unreachable image URL — returns an error if url_a or url_b cannot be fetched","Images with mismatched dimensions may produce unexpected results or an error","Payload exceeds 3MB threshold without store flag — automatically falls back to shareable link","Malformed base64 input causes decoding failure","Unsupported image format returns a format error"],"whenToPreferThis":"Use this endpoint when you need pixel-level visual regression testing between two images — especially for UI screenshots, design mockups, or any scenario where you need an exact quantified diff (count + percentage) and a visual red-highlight overlay. Prefer it over generic image similarity APIs when you need both a numeric metric and a rendered diff image. Best suited for automated QA pipelines, before/after deployment checks, and design review workflows.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-15T06:39:11.615Z","isFirstParty":false,"canonicalSlug":"agentrxi-image-diff-visual-regression-d57cf9c4"}