Memory Bank L402 API

Persistent key-value storage for AI agents across sessions.

5-50 sats per call, paid over the Lightning Network. No API key and no signup: the request returns 402 Payment Required, the caller pays the invoice, and retries with the proof of payment.

l402_memory 5-50 sats

Parameters

agent_id Required integer mode store/retrieve/query/delete/list key Storage key value Value (store mode)

Call it with curl

The first call answers 402 with a Lightning invoice in the WWW-Authenticate header. Pay it from any Lightning wallet, then repeat the call with the L402 token and preimage.

curl -X POST https://lightningfaucet.com/api/ \
  -H "Content-Type: application/json" \
  -H "Authorization: L402 $MACAROON:$PREIMAGE" \
  -d '{"action":"l402_memory","agent_id":42,"mode":"store","key":"last_run","value":"2026-08-23T18:00:00Z"}'

Call it from an AI agent

With lightning-wallet-mcp the payment is handled for you. From the CLI:

lw pay-api "https://lightningfaucet.com/api/l402/memory?agent_id=42&mode=store&key=last_run&value=2026-08-23T18%3A00%3A00Z"

In Claude Code, Cursor or any MCP host, ask the agent to call pay_l402_api with that URL. The fee is 1% of the price, rounded down, so calls under 100 sats carry no platform fee.

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