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WebRef Content-Type Advice
x402
WebRef Content-Type Advice is a paid API for AI agents from webref.johnaio281.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-22).
Returns content-type matching and MIME type guidance for HTTP GET, HEAD, or DELETE requests, including appropriate Accept headers and endpoint kind classification
Price / call$0.003
Success—
StatusUnknown
How this service works
Web standards and time reference for AI agents: HTTP status codes with what the client should do, retry semantics, MIME types and content-type matching, request-method safety and idempotency, plus deadline arithmetic - time until a moment, weekday and business-day checks, duration conversion and Unix timestamps. Pay per call in USDC on Base via x402 or USDC on Tempo via MPP. No signup, no API key, no KYC.
Output
Returns structured advice on appropriate MIME types, Accept headers, and content-type matching strategies for the specified HTTP method (GET, HEAD, or DELETE) and optional endpoint kind (json, form, multipart, xml, text, binary), helping agents configure HTTP requests correctly.
Example use cases
Correct MIME type for REST call
“I'm building an HTTP client that calls a JSON REST API with GET requests — what content type and Accept headers should I be sending?”
Content negotiation for XML endpoint
“I need to make a GET request to an XML data feed — what MIME type and content-type headers should I use for proper content negotiation?”
Binary file download header advice
“My agent is doing a GET request to download a binary file from a server — what content-type headers should it include to signal it can handle binary responses?”
Technical details
Endpoint
GEThttps://webref.johnaio281.workers.dev/api/web/content_type_advice?utm_source=zero.xyzWhen to prefer
Use this endpoint when an AI agent needs authoritative, lookup-based guidance on HTTP content-type and MIME type selection for GET, HEAD, or DELETE requests — especially in agentic pipelines that dynamically construct HTTP calls and need to set correct Accept or Content-Type headers without hardcoding web standards knowledge. Prefer this over general LLM knowledge when you need deterministic, up-to-date standards compliance with no hallucination risk.
Side effects
- Missing required 'method' parameter returns validation error
- Unsupported HTTP method (e.g. POST, PUT) rejected — only GET, HEAD, DELETE accepted
- Invalid endpointKind enum value returns error
- Payment not provided or insufficient USDC causes 402 response
- Network timeout on the Cloudflare Workers edge
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object |
Tags
x402
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