A2A Agent Card · AI Crawler Index

AI Crawler Index

Every AI crawler on the web, what it is for, what blocking it costs you, and the IP ranges its operator publishes — as JSON, CSV, robots.txt and regex. Ask it to identify a crawler from a raw User-Agent, look one up, list them by category or operator, generate a robots.txt for a stated stance, or check whether an IP address really belongs to the operator it claims. Deterministic and read-only: there is no model behind it — every answer comes from a public dataset rebuilt every six hours from each operator's own published documentation and IP ranges, and the same skills are also available as files under https://www.pathwren.workers.dev/ and as MCP tools at https://www.pathwren.workers.dev/mcp. No key, no signup, no quota. Independent and unaffiliated with any operator it documents.

✓ Conformant with A2A 1.0.0. This card passes every structural check in the A2A specification’s AgentCard object — a capabilities object, a declared protocolVersion, and a well-formed skills array.
Provider: AI Crawler Index Conformance: Conformant Protocol: 1.0 Transport: JSONRPC Version: 1.0.0 Host: www.pathwren.workers.dev Skills: 6
Discovery

An A2A client finds this agent by fetching the well-known path on the provider's own host. That is what makes an agent card different from every other agent artifact in this catalog: it is provider-published by construction — it cannot be derived, generated, or reconstructed on a provider's behalf.

https://www.pathwren.workers.dev/.well-known/agent-card.json
Interfaces
https://www.pathwren.workers.dev/a2a · transport · protocol JSONRPC non-standard supportedInterfaces
Skills (6)

Classify a user-agent string classify_user_agent

Identify the crawler behind a raw User-Agent header: operator, category, robots.txt stance, how to verify it, and what blocking it costs. A user-agent is a claim, not proof — confirm with is_verified_crawler_ip. Example: user_agent='GPTBot/1.2' returns GPTBot, OpenAI, ai-training.

user-agentcrawlersbot detectionidentification

Look up one crawler lookup_crawler

The full index record for one crawler: operator, category, robots.txt token and stance, user-agent substring and example, verification method, mirrored IP-range endpoint, and what blocking it costs. An unknown slug returns near matches. Example: slug='claudebot'.

crawlersreferencerobots.txtlookup

List and filter crawlers list_crawlers

The index, filtered or whole: each row says what the crawler is and what blocking it costs, and the reply lists every valid filter value. Example: category='ai-training', limit=20.

crawlerscataloguefilterdiscovery

Generate a robots.txt for a stance generate_robots_txt

A ready-to-paste robots.txt block for one stance, with the reasoning and the crawlers it names. Omit the argument to get all eight stances described. Example: stance='block-ai-training'.

robots.txtpolicyconfigurationgenerator

Check an IP against operator-published crawler ranges is_verified_crawler_ip

Test an IPv4 or IPv6 address against every crawler prefix the operators themselves publish, remirrored every six hours. Returns the matching prefix, its source and the crawlers using it; a miss is reported as a miss, not as a forgery. Example: ip='20.171.206.5'.

ip rangesverificationbot detectionsecurity

What changed in the index whats_changed

Freshness and change state: when the index was built, when each operator source was last fetched, which changed, which are failing, and the dated changelog. The cron check before regenerating a config from this data. Example: since='2026-08-01'.

freshnesschangelogmonitoringdata quality
Documentation
https://www.pathwren.workers.dev/a2a.html
Evidence. Fetched 2026-09-01 from https://www.pathwren.workers.dev/.well-known/agent-card.json, HTTP 200. The body was saved verbatim and is the sole source for everything on this page — no field is inferred. View the captured card. Providers change what they serve; if this card has moved or changed shape, the provider profile carries the current state as of the last build.

Work with this as data

Every agent card here is available over the APIs.io API and to AI agents over MCP. A2A Agent Cards 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

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https://apis.io/mcp

Tools for a2a agent cards

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=pathwren&limit=10"
Everything under a tag
curl "https://apis.io/api/v1/tags/pathwren"

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