# Typed HTTP structured-field composer

Build-time release reference. Runtime readiness, deployment, payment settlement and external indexing are not evaluated here. Prices are proposed; this file cannot authorize execution or payment.

Compose separate exact RFC 8941-compatible structured field values from explicit typed Items, Lists and Dictionaries; preserve decimal types without floating-point rounding.

Release: 0.29.0. Built: 2026-10-06T15:38:00Z.

## Choose for
- Composing caller-declared structured field name/value pairs for offline protocol fixtures
- Preserving ordered dictionaries and parameters with explicit string/token/bytes/integer/decimal/boolean types
- Rejecting decimal rounding, injection and duplicate keys before handoff

## Outside this profile
- Parsing existing fields, combining repeated lines or normalizing arbitrary headers
- Full RFC 9651 Date and Display String types; this explicit RFC 8941 vocabulary profile excludes them
- HTTP Message Signatures, signing, digest verification, authentication, cookies, header policy or application field semantics
- Raw HTTP header blocks, requests or transmission
- Network requests, writing files, live configuration changes, authentication, publishing or deployment

Proposed nominal USD 0.003 per successful call; payer fees excluded. No verified runtime availability.

- [Exact release contract](/reference/services/http-structured-fields-compose.json)
- [Input schema](/reference/schemas/http-structured-fields-compose.input.json)
- [Output schema](/reference/schemas/http-structured-fields-compose.output.json)
- [Fixed example](/reference/examples/http-structured-fields-compose.json)
- [Complete HTML reference](/discover/tools/http-structured-fields-compose)