# RCTP — Re-Commerce Trust Profile

> A profile of UCP (profiles, identity linking, message signatures, signed webhooks), OAuth 2.0, RFC 9421 and WebAuthn
> that lets AI agents trade used goods for people. Sellers grant an agent verbs and tiers (Agent Grant) and set private
> Listing Terms on a marketplace-hosted page that no agent ever sees; an enforcement point answers every agent call
> with auto (200/201), ask (202) or forbid (401/403/409/422/429) in the RCTP-Decision header.
> Status: Draft 0.4, pre-release. Release v0.2.0-draft.4 implements the Starter profile (capability version
> 2026-11-draft4, UCP v2026-08-25).

## Specification
- [Draft 0.4](spec/rctp-draft-0.4.md): normative text
- [v0.2 binding](spec/v0.2-binding.md): UCP profiles and request signing, Agent Grants, Listing Terms, offers, decisions, approvals, deal events, webhooks
- [Ambiguities](spec/AMBIGUITIES.md): readings chosen where the draft is unclear (B-1 to B-9)
- [Draft 0.3](spec/rctp-draft-0.3.md) and [v0.1 binding](spec/v0.1-binding.md): history (v0.1.0-draft.3)

## Docs
- [Quickstart](docs/quickstart.md)
- [Concepts](docs/concepts.md)
- [Decisions and errors](docs/decisions-and-errors.md): every reason code and what an agent should do next
- [Approvals](docs/approvals.md): hosted page, terms form, passkey approval
- [Versioning](docs/versioning.md)
- [Security](docs/security.md)
- [Extensions](docs/extensions.md)
- [FAQ](docs/faq.md)

## Code
- [Schemas](schemas/): JSON Schema 2020-12, source of truth
- [Registries](registries/): verbs and scopes, reason codes, term sets, approval levels, checkpoints, release conditions
- [TypeScript SDK](packages/sdk-ts/README.md): @rctp/sdk 0.2.0-draft.4
- [Python SDK](packages/sdk-py/README.md): rctp 0.2.0a4
- [Go gateway](packages/gateway-go/README.md): enforcement middleware, reference gateway, sandbox services
- [Sandbox](sandbox/README.md): docker compose, sandbox/smoke.sh
- [Conformance](conformance/README.md): Starter vectors V1–V15, V26–V29, S1–S4 and runner
- [Agent instructions](AGENTS.md)