API documentation

Base URL: https://h-gate.xr-utilities.ai

H-Gate inspects the data an agent is about to send across a boundary and applies your policy: allow, redact, or block. The engine is deterministic (pattern detectors plus checksum, entropy, and Luhn validation), with no model in the trust path. Inspection is a paid endpoint via x402; the config and health reads are free and unauthenticated.

POST /inspect

Inspect an outbound payload against the policy and return the decision (allow, redact, or block) with per-finding detail. Requires an x402 payment header; the fee is $0.10 per inspection. Every redact or block is anchored as an H-Seal receipt, and a denied send emits a risk signal onto the shared H-Series audit topic that feeds the sending agent's H-Cert standing.

Headers

X-Payment: <x402 envelope (base64)>
Content-Type: application/json

GET /config

Returns service configuration including the inspection price (inspectPriceUsdCents) and the accepted payment options across every supported chain.

Response 200

{
  "service": "h-gate",
  "inspectPriceUsdCents": 10,
  "accepts": [ ... ]
}

Payment

x402 payment

Payment for an inspection is handled via the x402 protocol. When a client calls /inspect without payment, the server responds with 402 Payment Required and a payment options envelope. The client selects a payment method, constructs a signed transaction, and resubmits with an X-Payment header containing the base64-encoded x402 envelope. Accepted rails are USDC on Hedera, Base, Solana, and Stellar, and RLUSD on the XRP Ledger.

MCP tools

H-Gate is exposed as MCP tools under the h_gate_* namespace via the shared H-Series MCP server at https://mcp.xr-utilities.ai/mcp. Agents can inspect a payload through the same policy engine as the REST API, with the identical x402 payment flow.