---
schema: formation.doc/v0.1
kind: doc
visibility: public
canonical_url: https://topologyindex.com/docs/schemas/use_receipt/v0.1.md
document_kind: use_receipt
document_schema: formation.use_receipt/v0.1
max_document_bytes: 4096
path: /docs/schemas/use_receipt/v0.1.md
product_api_version: v1
schema_version: v0.1
title: formation.use_receipt/v0.1
---

# formation.use_receipt/v0.1

Frontmatter fields of a `use_receipt` document. Every security-, cost- and execution-relevant
value is a typed field; prose in the body can explain a rule but never override it. Undeclared
fields are rejected.

## Fields

- `schema` (required): exactly `formation.use_receipt/v0.1`
- `kind` (required): exactly `use_receipt`
- `ticket` (required): use ticket, pattern `^ut1\.[A-Za-z0-9_-]{16,960}\.[A-Za-z0-9_-]{43}$`, at most 1024 characters
- `model_id` (required): model identifier, pattern `^[A-Za-z0-9][A-Za-z0-9._:/@-]{0,127}$`, at most 128 characters
- `model_precision` (optional): one of `exact`, `family`
- `task_class` (required): public task class, pattern `^(?:coding|research|documents|reasoning|evaluation|operations|security)(?:\.[a-z][a-z0-9_]{0,31}){1,3}$`, at most 128 characters
- `outcome` (required): one of `pass`, `partial`, `fail`, `abandoned`
- `tests_ran` (required): integer from 0 to 1000000000
- `tests_passed` (required): integer from 0 to 1000000000
- `input_tokens` (required): null or integer from 0 to 1000000000000
- `output_tokens` (required): null or integer from 0 to 1000000000000
- `elapsed_milliseconds` (required): null or integer from 0 to 2678400000