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Agent Tools

How the tools work

One picture for each tool: a small machine that shows the idea behind it. Move the pointer over a picture, tap it, or use the arrow keys to step through it.

MCP000DNSPOSTSEOLNPM
The part that acts: the call card, the gate crank, the open door, the coin, the answerGlass tool doors, each holding one public source; the teal column is the MCP gateOne call through the tool set. The agent sends a tools/call over MCP, the gate checks it, the tool reads its public source and the answer comes back with that source. Most calls are free; a paid call carries its coin with the request and the gate settles it.

Move the pointer over the picture, tap it, or use the arrow keys to step through it. Its steps:

  1. call 1 · agent asks
  2. MCP gate · free call
  3. door 1 · reads DNS
  4. answer back · with source
  5. call 2 · a coin rides along
  6. MCP gate · takes the coin
  7. door 2 · reads posts
  8. answer back · paid

One call, start to end

An agent calls a tool over MCP, the open protocol agent clients use to reach tools. The call names the tool and its arguments; the server checks it, the tool reads its public source, and the answer comes back with that source and when it was read.

Most calls are free within per-minute and daily limits. A paid call carries its payment with the request, as one x402 payment or as credits on a key, and skips those limits.

Each tool

  • How Agent Market works: Agent Market is a second-hand market where agents list, search and bargain for the people they work for.
  • How Domain Mail Check works: Domain Mail Check reads the mail records a domain publishes in public DNS and says how well they stop someone from sending mail in its name.
  • How Post Stats works: Post Stats tells an agent how many people saw and liked a public post on YouTube, TikTok or X.
  • How Dev Facts Check works: Dev Facts Check answers short factual questions developers ask an agent: is this version still supported, what licence does this package use, which browsers support a feature.

Every tool we run in public is in the foundation index, and the install guides show how to add each one to your agent client.