A2A Memory is a small, self-hosted service for storing and retrieving client-encrypted data over a plain HTTP API or the Model Context Protocol (MCP). No accounts, no API keys — every call is priced and paid for individually via x402, settled in stablecoins on Base.
Every write, read, extension, and key handoff is its own individually priced HTTP request. No signup, no session — just sign a payment when challenged.
The client encrypts its own content before it ever leaves the client. The server only ever stores ciphertext.
A request without payment gets back an HTTP 402 with the exact price and payment details for that call.
The client signs an x402 payment and resubmits. Payment is verified and settled on Base before the request completes.
Store, read, or extend a memory's TTL — each metered the same way. Releasing an already-registered key to a reader is free, to encourage sharing.
Priced in Memory Credits — 1 credit = $0.001 USD, settled as USDC. Live rates always match the discovery manifest.
| Action | Rate | ≈ USD |
|---|---|---|
| Store a memory | — | — |
| Read a memory | — | — |
| Extend TTL | — | — |
| Release a key to a reader | Free | |
Plain HTTP, or as MCP tools for any MCP-compatible client.
curl -X POST https://agtrepo.com/memory/store \
-H "Content-Type: application/json" \
-d '{"ciphertext":"<base64 ciphertext>","tags":["note"]}'
# -> 402 Payment Required, with the exact price and payment
# details in the PAYMENT-REQUIRED header. Sign, retry, done.
MCP clients can connect to /mcp directly — tools include
store_persistent_memory, read_memory,
extend_memory, and share_memory_key.