API reference · Receipts

Verify events

POST/v1/receipts/verify

Recompute the hashes of events you hold and check them against the record, plus signed provenance and evidence reports.

On this page

Auth. None. Without a token the call is served as Free (the Free delay and request budget, shared per IP); send Authorization: Bearer lb_… for your plan's.

Limits. Counts against your plan's API requests (60, 600 or 3,000 a minute on Free, Builder and Standard).

Parameters

Body

Name	Type	Required	Description
`events`	array of object	no	Events as you received them. Up to 500 items.
`reports`	array of object	no	Signed provenance reports or evidence packs. Up to 50 items.

Request

Terminal

curl -X POST "https://api.langbot.ai/v1/receipts/verify" \
  -H "Content-Type: application/json" \
  -d '{"events": [{"id": "evt_01K7Q0000000000000000000A2", "hash": "5d0e05c3…", "…": "…"}]}'

Python

from langbot import LangbotClient

async with LangbotClient() as lb:
    results = await lb.verify_receipts(events)  # recomputes locally, then asks the feed
    print(results)

TypeScript

const res = await fetch("https://api.langbot.ai/v1/receipts/verify", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({"events": [{"id": "evt_01K7Q0000000000000000000A2", "hash": "5d0e05c3\u2026", "\u2026": "\u2026"}]}),
});
console.log(await res.json());

Response

201 Created

JSON

{
  "results": [
    { "id": "evt_01K7Q0000000000000000000A2", "status": "match", "computed_hash": "5d0e05c3…", "stored_hash": "5d0e05c3…", "chain_ok": true, "chain_seq": 2, "checkpoint": { "chain_seq": 2, "key_id": "56475aa75463474c", "signature": "cEf385IN…" } }
  ]
}

status is match, mismatch or unknown. chain_ok says whether the stored prev_hash equals the stored hash one position earlier (null for the first event). No plan delay applies: you already hold the events.

Errors

Status	`code`	When
401	`token_invalid`	A token was sent and not recognised. Send a valid one, or none to call anonymously.
422	`validation_error`	A parameter failed validation; `detail[].loc` names it.
429	`rate_limited`	Over your request budget; wait `Retry-After` seconds.

Every error body is {"detail": …, "code": "…"}; branch on code. All codes: Errors.