# Licensing & Access Economics

> terms, compensation and gating

_3 of 28 · [all The Agent Protocol Atlas](/protocols)_

- [RSL](/protocols/licensing/rsl) — Machine-readable content-licensing terms, referenced from robots.txt — say which AI uses are free and which require a license or royalty.
- [Pay Per Crawl](/protocols/licensing/pay-per-crawl) — Cloudflare's HTTP 402-based mechanism that lets publishers charge AI crawlers per request — allow free, set a price, or block — with Cloudflare as merchant of record.
- [Content Signals](/protocols/licensing/content-signal) — A robots.txt extension that lets a site declare how its content may be used after access — search, ai-input, and ai-train — as machine-readable preferences.