facilitator-0.3.5 is not a library.

Facilitator

A production-ready CLI tool and HTTP server implementing the x402 payment protocol for blockchain-based micropayments.

Overview

The facilitator is a trusted third party that verifies and settles payments on behalf of resource servers. It does not hold funds — it only validates payment signatures and broadcasts settlement transactions on-chain.

Quick Start

# Install
cargo install facilitator

# Generate a default config file
facilitator init

# Edit config.toml with your RPC URLs and signer keys, then start
facilitator serve
facilitator serve --config my-config.toml

Docker

docker build -t facilitator .
docker run -p 8080:8080 -v ./config.toml:/app/config.toml facilitator

CLI

facilitator <COMMAND>

Commands:
  init   Generate a default TOML configuration file
  serve  Start the facilitator HTTP server

Options:
  -h, --help     Print help
  -V, --version  Print version

`init`

facilitator init [OPTIONS]

Options:
  -o, --output <PATH>  Output path [default: config.toml]
      --force          Overwrite existing file

`serve`

facilitator serve [OPTIONS]

Options:
  -c, --config <PATH>  Path to TOML config file [default: config.toml]

Configuration

The server loads configuration from a TOML file (default: config.toml). Run facilitator init to generate a commented template.

host = "0.0.0.0"
port = 8080

[chains."eip155:84532"]
rpc_url = "https://sepolia.base.org"
signer_private_key = "$EIP155_SIGNER_PRIVATE_KEY"

[[schemes]]
scheme = "v2-eip155-exact"
chains = ["eip155:84532"]

Environment Variables

Variable	Default	Description
`HOST`	`0.0.0.0`	Bind address
`PORT`	`8080`	Listen port
`CONFIG`	`config.toml`	Config file path (for `serve`)
`OTEL_*`	—	OpenTelemetry configuration

Endpoints

Method	Path	Description
`GET`	`/supported`	List supported payment kinds (version/scheme/network)
`POST`	`/verify`	Verify a payment payload against requirements
`POST`	`/settle`	Settle an accepted payment on-chain
`GET`	`/health`	Health check

Supported Chains

EVM (EIP-155) — Base, Ethereum, Polygon, Avalanche, Celo, and more
Solana (SVM) — Mainnet, Devnet, and custom clusters

Features

Feature	Default	Description
`chain-eip155`	✓	EVM chain support
`chain-solana`	✓	Solana chain support
`telemetry`	✓	OpenTelemetry tracing and metrics

Built With

r402 — x402 Payment Protocol SDK for Rust
r402-evm — EVM chain implementation
r402-svm — Solana chain implementation

License

This project is licensed under either of the following licenses, at your option:

Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project by you, as defined in the Apache-2.0 license, shall be dually licensed as above, without any additional terms or conditions.

facilitator 0.3.5