# Skills

> How to chain the endpoints of https://flat-rate-llm.kikoribera03.workers.dev instead of calling them one at a time. Each skill is a sequence of paid calls where **every answer names the next call with its parameters already filled in**, in a `next` array.

- [Check a domain end to end](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/domain.md) — Is this domain real, who owns it, does it work, and what does it serve? 5 calls, starting at `GET /v1/red/whois`.
- [Check an IP address end to end](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/ip.md) — Who holds this address, who announces it, and is it burnt? 3 calls, starting at `GET /v1/red/ip`.
- [Look up an EVM address end to end](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/wallet.md) — Whose address is this, what does it hold, and is it a person or a contract? 5 calls, starting at `GET /v1/evm/ens`.
- [Find out what a transaction did](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/transaction.md) — What did this transaction do, what did it cost, and who was on the other side? 4 calls, starting at `GET /v1/evm/tx`.
- [Check an ERC20 token before you trust it](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/token.md) — Is this token what it claims, what is it worth, and who can still change it under you? 5 calls, starting at `GET /v1/evm/token-info`.
- [Pick a chain and know what writing to it costs](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/evm-health.md) — Which chain is actually answering, is its head fresh, and what will a transaction cost right now? 4 calls, starting at `GET /v1/evm/chains`.
- [Turn a place into a time zone, and compare two clocks](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/time.md) — What is this place's zone actually called, what time is it there, and how far is it from another one? 3 calls, starting at `GET /v1/time/zones`.
- [Hear audio in another language](https://flat-rate-llm.kikoribera03.workers.dev/.well-known/skills/voice.md) — What does this recording say, in my language, and can I hear it read aloud? 3 calls, starting at `GET /v1/ai/transcribe`.

## Why this exists

The catalogue at `/llms.txt` says what each endpoint does. This says in what order to call them, which is the part an agent cannot guess.

## How paying works

- Call any endpoint with no payment. You get `402` with the challenge in the `PAYMENT-REQUIRED` header (base64, x402 v2).
- Sign an EIP-3009 authorisation for the amount stated and repeat the call with an `X-PAYMENT` header.
- Any x402 client does this for you. USDC on Base, Polygon or Arbitrum.