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Header category

Agent & Bot Identity

Headers by which an automated caller identifies itself, and by which a server decides what to serve it. The newest category, and the one with the least settled vocabulary.

8 headers
131 provider declarations
HeaderProvidersStatus
User-Agent 82 permanent
x-customer-user-agent 33 de-facto
Referer 11 permanent
From 5 permanent
Referer-Root obsoleted
Ping-To permanent
Ping-From permanent
Sec-Purpose permanent

All categories

Authentication Authorization & Scope Caching Conditional Requests & Concurrency Content Negotiation Representation Metadata Connection & Transport CORS Security Policy Privacy & Consent Rate Limiting & Quota Tracing & Correlation Idempotency & Reliability Versioning & Lifecycle Integrity & Signing Async & Long-Running Cost & Metering Agent & Bot Identity

Work with this as data

Every header here is available over the APIs.io API and to AI agents over MCP. HTTP Headers is not yet its own endpoint on the v1 API. Reach it through catalog search and the tag graph, or the MCP server.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for http headers

3 MCP tools reach this
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools →

Call it yourself

curl for this page
Search the catalog
curl "https://apis.io/api/v1/search?q=agent&limit=10"
Everything under a tag
curl "https://apis.io/api/v1/tags/agent"

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