# x402-vector

Memory for stateless agents. No accounts. The wallet that signs the x402 payment is the namespace owner.

Base URLs:
- Web/docs: https://x402vector.com
- API: https://api.x402vector.com
- OpenAPI: https://x402vector.com/openapi.json
- llms.txt: https://x402vector.com/llms.txt

Endpoint catalog:
- PUT /v1/memory: Use this when an agent needs to remember one compact JSON value under a stable key. Price: $0.002 USDC per call. URL: https://api.x402vector.com/v1/memory
- POST /v1/memory/batch: Use this when an agent has multiple memories to persist and wants one x402 settlement. Price: $0.05 USDC per call. URL: https://api.x402vector.com/v1/memory/batch
- GET /v1/memory/:key: Use this when an agent knows the exact key it wants to retrieve from its own wallet namespace. Price: $0.001 USDC per call. URL: https://api.x402vector.com/v1/memory/{key}
- POST /v1/search: Use this when an agent needs semantic recall but does not know the exact memory key. Price: $0.01 USDC per call. URL: https://api.x402vector.com/v1/search
- DELETE /v1/memory/:key: Use this to remove a memory item without paying. Sign x402-vector-delete:{key}:{unix-minute}. Price: Free. URL: https://api.x402vector.com/v1/memory/{key}
- GET /v1/namespace: Use this free endpoint to check whether a wallet namespace still has active or grace-period state. Price: Free. URL: https://api.x402vector.com/v1/namespace

Payment and auth:
- Paid endpoints use x402 v2 on Base. Send PAYMENT-SIGNATURE for signed payments; legacy X-PAYMENT is also accepted.
- Omit the payment header to receive a 402 quote containing the exact payment requirements.
- DELETE /v1/memory/:key is free and requires X-WALLET-ADDRESS plus X-WALLET-SIGNATURE over x402-vector-delete:{key}:{unix-minute}.
- GET /v1/namespace is free and public. It returns only non-sensitive namespace metadata.

Data and lifecycle:
- Values are JSON-serializable and limited to 10240 bytes. Batch writes accept up to 100 items. Paid activity renews namespace rent for 30 days; after expiry, a 14-day grace window applies before deletion. Search topK defaults to 10 and is capped at 50.
- Handler validation failures and not-found responses are not charged because x402 settlement only happens after successful handler responses.
- Refunds are operator-reviewed ledger entries for async write failures after a settled 200. The service does not automatically send refunds.

Recommended flow:
1. Use PUT /v1/memory for exact-key memory writes.
2. Use GET /v1/memory/:key for exact recall.
3. Use POST /v1/search for semantic recall when the key is unknown.
4. Use GET /v1/namespace?address=0x... to check rent status before deciding whether to pay for another call.