Example inputPOST /api/v1/x402/x402-idempotency-check
{
"payment_key": "job-42",
"delivery_key": "job-42"
}Portable intent card · commercial-operations
X402 Idempotency Check API for agents
X402 Idempotency Check: X402 Idempotency Check compares payment and delivery idempotency keys for one operation from bounded caller-supplied values without an external provider. Call X402 Idempotency Check before paying for or accepting an x402 or agent delivery assembled from caller-supplied challenge and result metadata. Returns contract-specific checks, normalized evidence, mismatch reasons, and an explicit acceptance or rejection status for X402 Idempotency Check as versioned deterministic JSON. Price: $0.001 USDC via x402 on Base. First-party, stateless, memory-only execution with no paid upstream, live RPC, web search, credentials, custody, signing, media generator, or input retention. Honest limit: Validates metadata only; it never settles payment, signs payloads, contacts a facilitator, refunds funds, or asserts on-chain truth. Advisory output only; the buyer owns authorization, payment policy, and production decisions.
Intent to transaction
One command, attributed.
The source header follows this discovery route through challenge, payment and delivery without exposing the buyer or request body.
npx agentcash@latest fetch https://api.delx.ai/api/v1/x402/x402-idempotency-check -m POST -H 'x-delx-source: intent-card-x402-idempotency-check-api' --max-amount 0.001 -b '{"payment_key":"job-42","delivery_key":"job-42"}'Agent discoverydelx/intent-card/v1
{
"intent": "X402 Idempotency Check for an agent workflow",
"tool_name": "util_x402_idempotency_check",
"price_usdc": "0.001",
"machine_url": "https://commerce.delx.ai/intents/x402-idempotency-check-api.json"
}Portable and inspectable