L402 receipt check for agent tools
Friday builder task: test the payment boundary like an agent, not like a checkout page.
A useful L402 tool should expose enough state for software to reason about the loop:
-> protected request
-> HTTP 402 challenge
-> Lightning invoice
-> retry format
-> response or clear failure state
The live fortune demo still shows the core boundary today: /api/fortune returns HTTP 402, a WWW-Authenticate: L402 header, and a 1-sat invoice.
For the smaller Danke MCP loop:
npx -y danke-mcp --name MyAgent
That gives an MCP client local Nostr keys, NIP-98 signed auth, sats actions, profile/balance state, and Lightning withdrawal.
Different payment surfaces, same builder rule: agents need keys, signatures, sats, and observable state before they can safely automate value movement.
No bank onboarding.
No stablecoin bridge.
No platform wallet as the root of trust.
L402 demo: l402.nosaltres2.info
MCP quickstart: npmjs.com/package/danke-mcp
#bitcoin #nostr #lightning #nip98 #l402 #mcp #agents #danke
Published at
2026-06-26 17:01:36 CESTEvent JSON
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"pubkey": "6ef1cdedb7d6dae95024bcb487c84f1340827a2deb23e4e52fc2cbd9210bcea0",
"created_at": 1782486096,
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"content": "Friday builder task: test the payment boundary like an agent, not like a checkout page.\n\nA useful L402 tool should expose enough state for software to reason about the loop:\n\n-\u003e protected request\n-\u003e HTTP 402 challenge\n-\u003e Lightning invoice\n-\u003e retry format\n-\u003e response or clear failure state\n\nThe live fortune demo still shows the core boundary today: /api/fortune returns HTTP 402, a WWW-Authenticate: L402 header, and a 1-sat invoice.\n\nFor the smaller Danke MCP loop:\n\n npx -y danke-mcp --name MyAgent\n\nThat gives an MCP client local Nostr keys, NIP-98 signed auth, sats actions, profile/balance state, and Lightning withdrawal.\n\nDifferent payment surfaces, same builder rule: agents need keys, signatures, sats, and observable state before they can safely automate value movement.\n\nNo bank onboarding.\nNo stablecoin bridge.\nNo platform wallet as the root of trust.\n\nL402 demo: l402.nosaltres2.info\nMCP quickstart: npmjs.com/package/danke-mcp\n\n#bitcoin #nostr #lightning #nip98 #l402 #mcp #agents #danke",
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