hen 0.20.2

Run protocol-aware API request collections from the command line or through MCP.
Documentation
---
title: Language Reference
description: Task-focused reference pages for Hen authoring syntax, selectors, assertions, and protocols.
slug: /reference
---

Hen's web reference is organized as task-focused pages so you can jump directly to the part of the
language you are authoring.

## Reference Sections

- [Variables and environments]./variables-and-environments.md
- [Secrets and redaction]./secrets-and-redaction.md
- [Requests and bodies]./requests-and-bodies.md
- [Reliability]./reliability.md
- [JSON selection]./json-selection.md
- [Captures and assertions]./captures-and-assertions.md
- [Protocols]./protocols.md
- [Schemas]./schemas.md
- [Dependencies, fragments, and callbacks]./dependencies-fragments-callbacks.md

## Suggested Path

 - Start with [Getting Started]../getting-started/index.md or the
   [Syntax Cheatsheet]../getting-started/syntax-cheatsheet.md when you want the basics first.
 - Start with [Variables and environments]./variables-and-environments.md when you are defining
  inputs, prompts, or named environments.
- Use [Requests and bodies]./requests-and-bodies.md, [Reliability]./reliability.md, and
  [Captures and assertions]./captures-and-assertions.md for ordinary HTTP authoring.
- Use [Protocols]./protocols.md when you need GraphQL, SSE, or WebSocket behavior.
- Use [Recipes]../recipes/index.md when you want runnable collections alongside the reference.