Lodestar Stamp

For agents · pilot edition

Check before you book.

A person asks an assistant for someone to fix the furnace tonight. The assistant names three companies. Before it books, it calls the Stamp for all three. One receipt may say the licence is not verified, with the register and the date we looked. The assistant says so. On the record. We never approve the booking.

Charter: On the record. We do not approve the booking. Payment never touches the record. Nothing on the record is for sale.

The loop

  1. Batch the shortlist. One call, up to twenty domains, answered in the order asked, never sorted: the batch_receipts MCP tool (npx -y lodestar-stamp-mcp@0.1.17), or GET endpoints.trust from the discovery card for each domain. /index.json is a published edition snapshot, not the request-time receipt.
  2. Verify offline. Each signed receipt is checked against GET https://lodestarstamp.com/v1/keys. A valid signature says the bytes came from Lodestar. It never tells the assistant whether to book.
  3. Read receipt.fields. verified is what we checked on that date. not_published is coverage, not a finding. The receipt says the same on the wire: how_to_read carries one sentence per state, and the 300, the 404 and the batch envelope carry theirs. Then you decide.
  4. Optional: GET /changes.json on this host (or filter via the Trust API) to review published changes. Re-fetch the receipt and check its expiry before each decision.

Header, never required: X-Lodestar-Consumer: your-tool-name. It counts the integration and does not change the receipt.

Run it

Three covered Chicago HVAC domains. The client prints whatever the live receipts say. It does not invent a lapsed licence.

Download either standalone client: Python client or JavaScript client. No repository access is needed. Run the matching command from your download folder. Both clients send your key from LODESTAR_KEY, so these three reads use its free reads; they never pay, and a read that does not answer 2xx is printed with its status.

python3 check_before_you_book.py oasisheating.com,myheroair.com,air-rite.com --consumer my-agent
node check_before_you_book.mjs oasisheating.com,myheroair.com,air-rite.com --consumer my-agent

Use Python 3.10+ or Node 22+. Python reads receipts with its standard library; install cryptography to verify Ed25519 signatures. The Node client verifies them without additional packages. A valid signature establishes who signed the bytes, not whether a booking is appropriate.

Or MCP: Streamable HTTP at https://api.lodestarindex.com/mcp (unkeyed initialize / tools/list / tools/call). Optional stdio: npx -y lodestar-stamp-mcp (pin lodestar-stamp-mcp@0.1.17), or Add to Cursor. Do not paste /.well-known/mcp.json into Cursor or Claude as the MCP server — that file is a Trust API discovery card. Then find_business by name or street and get_receipt for each match; list_sources and list_gaps project the same receipt.

The downloads contain the complete source for inspection. Read the API documentation.

Paste this into an assistant

The same loop, as instructions. Copy as-is. Do not add rank, approval, or a score.

You are about to name Chicago HVAC companies for someone who needs a furnace fixed tonight.

1. Name up to three businesses you would consider.
2. Before anyone books, call Lodestar Stamp for the shortlist:
   Use the batch_receipts MCP tool (stdio: npx -y lodestar-stamp-mcp) for up to twenty domains,
   or GET endpoints.trust from https://lodestarstamp.com/.well-known/mcp.json for each domain.
   Do not treat /index.json as the request-time receipt.
   Header when calling the API: X-Lodestar-Consumer: your-tool-name
3. For each 200, read receipt.fields. Tell the person the dated facts: real, at that address, licensed, each with state, source, verified_on and expires_on. A field that is not_published has nothing to report this edition. If you only have the published edition snapshot, a verified field whose expires_on is already past is stale — stop.
4. If licensed is not verified, say so before anything is booked.
5. Do not rank. Do not approve. The person decides.

Install: npx -y lodestar-stamp-mcp
Download the Python client from https://lodestarstamp.com/check-before-you-book first. Then: python3 check_before_you_book.py oasisheating.com,myheroair.com,air-rite.com --consumer your-tool-name
Walkthrough: https://lodestarstamp.com/check-before-you-book

Price

Every receipt is free to read on lodestarstamp.com. Programmatic reads (API and MCP) are metered: $1 per read, with 10 free reads a month per credentialed identity. Past the free reads, or with no credential, a read answers HTTP 402 with an x402 payment request. Trial keys are available for integration review; volume terms are agreed per contract. Request trial access. Agent read terms.