Pay per request with x402

Let agents pay selected longevity API routes directly on Base, Polygon, or Solana without creating an API key.

ForeverBetter supports x402 v2 as an optional authorization path for agent-friendly API calls. An agent can discover a capability, pay a small USDC amount, and receive the response without an account, subscription, or API key.

API keys remain the best choice for sustained use. If a request includes an Authorization header, ForeverBetter uses normal bearer authentication and does not invoke or charge x402.

Payment flow

1. Call an x402-enabled route without an API key.
2. Read the base64-encoded x402 v2 object from PAYMENT-REQUIRED on the 402 response.
3. Choose an accepted network and sign the payment with an x402 client.
4. Retry the same request with the encoded payload in PAYMENT-SIGNATURE.
5. Read settlement details from PAYMENT-RESPONSE on the successful response.

curl -i "https://api.foreverbetter.xyz/providers?modality=genetics"
# HTTP/2 402
# PAYMENT-REQUIRED: <base64 x402 v2 requirements>

curl -i "https://api.foreverbetter.xyz/providers?modality=genetics" \
  -H "PAYMENT-SIGNATURE: <signed x402 payload>"
# HTTP/2 200
# PAYMENT-RESPONSE: <base64 settlement response>

Use an official x402 buyer SDK to decode, select, sign, and retry automatically. The protocol uses CAIP-2 network identifiers:

Network	CAIP-2 identifier
Base mainnet	eip155:8453
Polygon mainnet	eip155:137
Solana mainnet	solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp

Private wallet workspace

A verified payer address becomes a deterministic, private ForeverBetter identity. Base and Polygon share the eip155 address namespace, so the same EVM wallet can import on Base and analyze or read the result after paying on Polygon. Solana addresses use their own namespace.

This is an authorization boundary, not merely a billing label. A wallet cannot pay to read another wallet’s sources, analyses, ancestry results, or dashboard specifications. For x402 requests, omit user_id and organization_id; ForeverBetter fills them from the verified payer.

Enabled capabilities

The live deployment is authoritative. Read GET https://api.foreverbetter.xyz/.well-known/x402.json for enabled networks, facilitators, route templates, and prices. The implementation supports:

• Provider and lab search
• Small multimodal imports through POST /imports/file
• Multimodal and modality-specific analyses
• Reading wallet-owned sources and analyses
• Recommendations and action plans
• Renderer-neutral dashboard specifications
• Grounded health queries
• Ancestry analysis from a wallet-owned genetics source

Account administration, API-key issuance, billing, wearable OAuth, provider token exchange, private share links, exports, deletion, and direct WGS upload sessions intentionally remain API-key-only. They either establish durable authority, connect third-party accounts, or have consequences that should not be authorized by a one-off payment.

Bazaar discovery

Every paid route declares the x402 Bazaar extension with an input example, input schema, output example, service name, and topical tags. Dynamic paths use :param route templates. For example, calls to /analyses/an_123/action-plan and /analyses/an_456/action-plan are cataloged as one resource:

/analyses/:id/action-plan

The extension adds the concrete value under pathParams while the facilitator uses routeTemplate as the stable catalog key. Agents can search a Bazaar-enabled facilitator through its /discovery/resources endpoint. See the official Bazaar dynamic-route specification.

Self-hosting

x402 is disabled unless every required value is configured:

X402_ENABLED=true
X402_NETWORKS=base,polygon,solana
X402_FACILITATOR_URLS=https://facilitator-one.example,https://facilitator-two.example
X402_EVM_PAY_TO=0xYourBaseAndPolygonAddress
X402_SOLANA_PAY_TO=YourSolanaAddress

The configured facilitators may be separate services. Collectively their /supported responses must advertise x402 v2 exact settlement for every enabled network. When multiple facilitators advertise the same network, the first URL has precedence. The default public x402.org facilitator is intended for testnets, so do not use it as an implicit mainnet production default.

Coinbase CDP mainnet uses dynamically signed authentication rather than a static bearer header. Include its production URL and configure both credentials as deployment secrets:

X402_FACILITATOR_URLS=https://x402.polygon.technology,https://api.cdp.coinbase.com/platform/v2/x402
CDP_API_KEY_ID=organizations/.../apiKeys/...
CDP_API_KEY_SECRET=...

With the ordering above, Polygon payments use Polygon’s facilitator and the CDP facilitator handles Base. CDP can also provide Solana once a Solana payout address is configured.

Override prices with a JSON object keyed by ForeverBetter endpoint ID or route:

X402_ROUTE_PRICES={"imports.file":"$0.02","analyses.create":"$0.05","genetics.ancestry.create":"$0.10"}

If a facilitator requires static headers, store the JSON value of X402_FACILITATOR_AUTH_HEADERS as a deployment secret. Never commit facilitator credentials or payout-wallet private keys. ForeverBetter needs only public recipient addresses; payment signing stays with the paying agent.

Fulfillment guarantees

ForeverBetter verifies the payment before executing the route, buffers the endpoint response, and settles only after successful fulfillment. Handler errors cancel the verified payment flow and return the normal API problem response without PAYMENT-RESPONSE.

For paid POST routes, ForeverBetter derives an idempotency key from the signed payment when the caller does not provide one. Retrying the same signed payment therefore replays the original write instead of creating a duplicate import or analysis. Solana duplicate-settlement protection is delegated to the configured x402 facilitator and the official SVM mechanism.