Core Syntax

The core syntax — request lines, headers, body, separators, and comments — is the most portable part of the .http format.

Feature	VS Code	JetBrains	httpyac	VS 2022	kulala
Request line (METHOD URL [HTTP-version])	✓	✓	✓	✓	✓
Method defaults to GET when omitted	✓	✓	✓	✓	✓
Multi-line URLs via indentation Continuation lines beginning with whitespace are concatenated to the URL.	✓	✓	✓	✗	✓
HTTP/2 version VS Code REST Client does not document HTTP/2 support.	✗	✓	✓	✓	✓
HTTP/2 (Prior Knowledge) Direct HTTP/2 without upgrade negotiation.	✗	✓	✗	✗	✗
HTTP/3 version Unique to Visual Studio 2022.	✗	✗	✗	✓	✗
Request separator (###)	✓	✓	✓	✓	✓
Line comments (#)	✓	✓	✓	✓	✓
Line comments (//)	✓	✓	✓	✓	✓
Block comments (/* */) Unique to httpyac.	✗	✗	✓	✗	✗
Text after ### as request title	✗	✓	✓	✗	✓
Request headers (Name: Value)	✓	✓	✓	✓	✓
Multi-line header values via indentation	✗	✓	✓	✗	✗
Spread headers (...variableName) Injects all key-value pairs from an object variable as headers.	✗	✗	✓	✗	✗
Request body after blank line	✓	✓	✓	✓	✓
URL-encoded form body with & prefixes	✓	✓	✓	✓	✓

What's universal

Every client supports:

• METHOD URL [HTTP-version] request lines with GET as the default method
• Name: Value headers terminated by a blank line
• Request body after the blank line
• ### request separators
• # and // line comments
• {{variableName}} substitution
• @var = value inline variable definitions

Key differences

Multi-line URLs

All clients except Visual Studio 2022 support breaking long URLs across lines with indentation:

GET https://example.com/api
  /users
  ?page=2
  &limit=10

HTTP versions

HTTP/2 (Prior Knowledge) is JetBrains-only. HTTP/3 is VS 2022-only.

Separator titles

JetBrains, httpyac, and kulala.nvim treat text after ### as a request title. VS Code REST Client and VS 2022 treat it as a comment.

Block comments

Only httpyac supports /* ... */ block comments.

Syntax details: File Basics, Requests, Separators & Comments.