A clear handoff.
Exact bytes.

The download

Make a handoff. Check what arrived.

Node.js 22+ source compatibility; tested with Node.js v24.20.0 on macOS. Node.js 22 has not been directly tested.

For agent buyers

Keep payment and recovery together.

1. Read the exact offer. JSON offer, agent guide and OpenAPI describe the fixed one-time price and endpoints. For a quote, omit PAYMENT-SIGNATURE and Authorization. When checkout is available, this GET returns a standard x402 v2 402 price challenge without paying. When new checkout is unavailable, the quote GET returns 503 before any payment; do not sign or authorize a new purchase. Bearer-only recovery of an existing order remains available.
2. Let your agent save a private recovery key before payment. Use a client that automatically generates 256 random bits as 64 lowercase hex characters and saves them in its private local journal. Include the key as X-Lumen-Recovery-Key on the sole approved paid call; a missing key returns 428 before settlement. An exported original signature is an optional backup. This public browser generates no key and signs no payment.
3. Confirm, then download privately. Save the returned order ID and receipt; check its payer, recipient, Base network and exact amount. A 200 response gives a private download URL; use Authorization: Bearer <your saved key>, then verify the ZIP size and SHA-256. Neither a public transaction hash nor signed onchain proof alone is enough. No raw recovery key is echoed.
4. Recover a lost reply without paying again. On 202 or a lost or uncertain reply, send GET /api/wares/agent-delivery-manifest-kit-v1/purchase with Authorization: Bearer <your saved key> and no payment signature. This read recovers the existing order, receipt and download URL even while new checkout is unavailable. No order ID, nonce or exported signature is needed. Never invoke a payment tool again for recovery. Never put your key in a URL or email it.

New authorization attempts are limited to 600 globally per calendar month and 10 per minute per hashed IP. Recovery reads, including unknown-key locator attempts: 30 per source per minute and 300 globally per minute. On 429, wait for Retry-After, then use the saved key for a Bearer-only recovery read.

Alternative card method

USD 1.00 with Stripe MPP.

One download of the same kit. The 0.10-USDC option remains unchanged. Lumen House on Stripe is the merchant profile.

1. Save recovery before the challenge. Your agent must support Stripe-issued card Shared Payment Tokens and MPP. Generate and durably save a private 256-bit key, encoded as 64 lowercase hex. GET /api/wares/agent-delivery-manifest-kit-v1/purchase/card with X-Lumen-Recovery-Key and no Authorization. Compare the JSON and WWW-Authenticate: Payment challenge; check USD 100 cents, expiry, externalId and live networkId profile_61VYCfI53BDBE2tqkA6VYCfH0lSQNTlKRsBmcLHRATku.
2. Approve one card purchase. Obtain a scoped card SPT and check buyer/issuer fees before authorizing. Save a permanent local submission marker, then send one GET to that same URL with the saved recovery header and Authorization: Payment <MPP credential>. Do not send an x402 signature here. The public preview collects no card details and does not submit a browser card payment.
3. Verify, then download. A settled 200 contains the succeeded USD receipt, Payment-Receipt and private ZIP URL. Check amount_received 100, live mode, order/profile/product/hash. GET the returned /api/card-downloads/{order_id} URL with the saved key as Bearer; verify the same ZIP size and SHA-256.
4. Recover without a new financial call. After 202, timeout or a lost reply, GET /api/wares/agent-delivery-manifest-kit-v1/purchase/card with Authorization: Bearer <saved key> only. Omit the recovery header and Payment credential. This existing-order lookup works while new checkout is held. Never issue another token or invoke a payment tool again to recover.

Complete card and USDC agent guide · Machine contract

A missing recovery key returns 428 before a financial call. A five-minute unpaid challenge does not refresh after dispatch. Pending search results never justify paying again. Minimum private recovery: 30 days; same support/refund request terms.