# Axiom Relay

> An x402 smart router for autonomous agents. Give it a capability rather than a
> URL: it discovers x402 providers, validates that they are live, ranks them on
> price and reliability, pays the seller directly, and returns the result.
> Non-custodial and keyless — Axiom never holds buyer or seller funds.

Pricing: 3% of the seller price, capped at $0.50 per purchase. No minimum
fee. A fee too small for the facilitator to settle is waived and the purchase is
routed free while free-routing capacity remains.

Protocols: x402 v2 (`exact` scheme), Base mainnet (eip155:8453) and Base
Sepolia (eip155:84532), USDC. Model Context Protocol. A2A Agent Card.

## Endpoints

- [Machine descriptor](https://axiom-relay.reference-seller.workers.dev/.well-known/x402): capabilities, pricing, schemas, availability
- [Route by capability](https://axiom-relay.reference-seller.workers.dev/v1/route): POST a capability, receive ranked providers and a signed quote
- [Quote a URL](https://axiom-relay.reference-seller.workers.dev/v1/quote): POST a known x402 resource URL, receive its price and Axiom's fee
- [Execute](https://axiom-relay.reference-seller.workers.dev/v1/request): POST a quote plus signed authorisations
- [Health](https://axiom-relay.reference-seller.workers.dev/health): status, network, facilitator, gates
- [Provider listing](https://axiom-relay.reference-seller.workers.dev/v1/discovery): Bazaar-style resource entry for this relay

## Documentation

- [OpenAPI 3.1](https://axiom-relay.reference-seller.workers.dev/openapi.json): complete request and response schemas
- [SKILL.md](https://axiom-relay.reference-seller.workers.dev/SKILL.md): when and how an agent should use Axiom
- [A2A Agent Card](https://axiom-relay.reference-seller.workers.dev/.well-known/agent-card.json): agent-to-agent capability descriptor
- [MCP manifest](https://axiom-relay.reference-seller.workers.dev/.well-known/mcp.json): Model Context Protocol tools
- [Source and SDK](https://github.com/Itr3k/axiom-relay)

## Notes for implementers

- Sign with the standard x402 SDK. Axiom never receives a private key.
- When `feePolicy` is `fee_waived_micropayment`, omit the fee authorisation.
- `free_route_quota_exhausted` means Axiom's free capacity is spent, not that
  the purchase or provider is invalid.
- Fallback advances only on positive evidence the previous seller was unpaid;
  an ambiguous settlement halts the attempt chain.

## Axiom Crypto (beta)

Non-custodial crypto routing for autonomous agents. Axiom compares execution routes, validates transaction safety and total cost, and returns transactions for the agent to sign. Axiom never takes custody and never signs.

Execution providers: LI.FI
Chains: Ethereum, Base, Arbitrum One, OP Mainnet
Assets: ETH, USDC, USDT, WETH
Fee: 15 bps, embedded integrator fee, collected by the execution provider during the swap
Quote: POST https://axiom-relay.reference-seller.workers.dev/v1/crypto/quote
Analyze (no transaction returned): POST https://axiom-relay.reference-seller.workers.dev/v1/crypto/analyze

- Beta: conservative trade and daily volume ceilings apply
- Axiom never takes custody of principal
- Axiom never signs a customer transaction and holds no customer key
- Approvals are exact-amount; unlimited approvals are refused
- Slippage is never widened beyond what the caller specified
- Route calldata is validated against the request, not trusted from the provider
- Selection is deterministic and the reason is returned with every quote
- Provider fees and Axiom's fee are disclosed separately, never as one figure