Ashlar Blue Developer Documentation

# Platform Overview

Ashlar Blue addresses the fundamental constraint of machine-to-machine commerce: transaction graph surveillance and counterparty risk. When autonomous agents transact on public blockchains, their financial graphs, balances, and operational strategies are exposed to public surveillance.

Ashlar Blue unifies three core technologies into a single non-custodial clearing layer:

• Hardware Enclaves (AMD SEV-SNP & Intel TDX): Cryptographic clearing, signature validation, and trade matching execute within hardware-isolated memory perimeters inaccessible to hosts, cloud providers, or operators.
• Dual-Stack x402 Facilitator: Gasless micropayment routing using canonical EIP-3009 authorizations and IETF DNS discovery.
• IETF SCITT Transparency Receipts (RFC 9162): Every settlement emits a merkleized audit receipt that institutions and regulators can verify offline without calling APIs.

# 5-Minute Quickstart

To interact with an x402 paywalled resource on Ashlar Blue, follow the two-step handshake:

Step 1: Probe the Resource for the 402 Challenge

Send an unauthenticated request to the paywalled endpoint. The server responds with HTTP 402 Payment Required containing the accepted payment methods and pricing in the canonical payment-required header:

curl -i -X POST https://api.ashlar.blue/demo/card

Step 2: Interactive Live Endpoint Probe

Test the live facilitator endpoint directly from this documentation portal:

# The x402 Protocol Wire Specification

Ashlar Blue operates a dual-stack x402 v1 / v2 facilitator. In x402 v2, payment requirements are delivered in the payment-required Base64 response header:

HTTP/2 402 Payment Required
Content-Type: application/json; charset=utf-8
Access-Control-Expose-Headers: payment-required
payment-required: 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

Decoded, the challenge contains an array of acceptable offers identified by CAIP-2 network identifiers:

# DNS Discovery Specification (_x402)

Autonomous AI agents discover facilitator endpoints without centralized registries by querying standard DNS TXT records defined under the IETF x402 DNS Discovery draft.

To announce an x402 facilitator for a domain, configure the _x402 apex record:

_x402.ashlar.blue. IN TXT "v=x402-1; wk=https://api.ashlar.blue/.well-known/x402; k=facilitator; net=eip155:114; scheme=exact"

# Hardware Enclave Silicon & Remote Attestation

All clearing decisions and cryptographic verifications on Ashlar Blue execute inside attested hardware execution environments: AMD SEV-SNP and Intel TDX.

Verifying Remote Attestation

Integrators can independently verify the enclave's code integrity using the verify_tdx_quote or get_enclave_attestation tool over the Model Context Protocol (MCP) or via our public API endpoint.

# Model Context Protocol (MCP) Server

Ashlar Blue provides a full-featured MCP server (@ashlar-blue/x402-trust) enabling autonomous AI assistants—such as Claude Code, Cursor, and Google Antigravity—to discover paywalls, verify enclave attestation, and dispatch gasless payments.

{
  "mcpServers": {
    "ashlar-trust": {
      "command": "npx",
      "args": ["-y", "@ashlar-blue/x402-trust", "mcp"]
    }
  }
}

Core Tool Reference

# REST API Reference

The facilitator server exposes clean HTTP endpoints for verification, settlement, and resource delivery.

POST /verify

Pre-verifies an EIP-3009 authorization before broadcast to confirm signature validity, nonce status, and sufficient balance.

curl -X POST https://api.ashlar.blue/verify \
  -H "Content-Type: application/json" \
  -d '{
    "x402Version": 2,
    "paymentPayload": {
      "from": "0x118970D2b9c36fB65Eb00F0203Ad5DF...",
      "to": "0x3c36450b84b7b9712A396ab4e1b551888ab36599",
      "value": "100000",
      "validAfter": 0,
      "validBefore": 1788700000,
      "nonce": "0x8f2d...",
      "v": 27,
      "r": "0x...",
      "s": "0x..."
    }
  }'

GET /supported

Returns the live array of supported blockchain networks, tokens, and hardware enclave environments.

{
  "networks": [
    { "name": "coston2", "caip2": "eip155:114", "type": "evm" },
    { "name": "flare", "caip2": "eip155:14", "type": "evm" },
    { "name": "songbird", "caip2": "eip155:19", "type": "evm" },
    { "name": "xdc", "caip2": "eip155:50", "type": "evm" }
  ],
  "enclaves": ["GCP_AMD_SEV", "INTEL_TDX_V4"],
  "standards": ["x402-v2", "EIP-3009", "RFC-8785", "IETF-SCITT-RFC-9162"]
}