{"uid":"cap_Vx8CckF1wJ3J1OsSl1JOL","slug":"image-captioner-by-pdf-extract-api-e5f723a7","name":"Image Captioner by PDF Extract API","description":"Generate a caption, alt text, tags, and dominant colors for an image.","url":"https://image-captioner.pdfextractapi.workers.dev/caption","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"required":["file"],"properties":{"file":{"type":"string","format":"binary"}}},"type":{"type":"string","const":"http"},"method":{"enum":["POST"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_M_-cjIQcL-QgwrCoHW71R","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Analyzes an uploaded image and returns a human-readable caption, alt text, descriptive tags, and dominant colors.","exampleAgentPrompt":"Can you analyze this image file and give me a caption, alt text, a list of descriptive tags, and the dominant colors in it?","exampleUseCases":[{"title":"Accessibility alt text for web images","prompt":"I'm uploading a product photo to my website — can you generate proper alt text and a short caption for it so it's accessible to screen reader users?"},{"title":"Auto-tagging e-commerce product images","prompt":"I have a batch of product images I need to organize — can you analyze this image and give me tags and dominant colors so I can categorize and filter it in my catalog?"},{"title":"Social media caption generation","prompt":"I just took a photo I want to post — can you look at this image and write a caption for it, plus tell me what tags and colors stand out?"}],"resultDescription":"The endpoint returns a structured response containing a generated natural-language caption describing the image, alt text suitable for accessibility use, a list of descriptive tags, and the dominant colors present in the image.","failureModes":["Missing or malformed image file returns an error — file field is required","Unsupported image format may cause processing failure","Large file sizes may exceed Cloudflare Worker limits and result in a timeout or error","Invalid body type (not form-data with binary file) causes schema validation failure","Network timeout if image processing takes too long"],"whenToPreferThis":"Choose this endpoint when you need to enrich image assets with metadata — especially caption text, accessibility alt text, content tags, and color palette — in a single call without setting up your own vision model pipeline. It is well-suited for content management, e-commerce cataloging, and accessibility workflows where you need structured image descriptions quickly and cheaply at $0.02 per image.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:35:46.902Z","isFirstParty":false}