Markdown

Markdown messages carry rich text on Browser, Node, Kotlin, and Swift.

Type ID: xmtp.org/markdown:1.0. The payload is UTF-8 bytes with an encoding parameter. It has no fallback. shouldPush defaults to true. All four SDKs include MarkdownCodec.

The codec transports Markdown text. Your renderer determines which syntax it supports. Treat received Markdown as untrusted input. Sanitize rendered HTML.

In the Agent SDK, use ctx.conversation.sendMarkdown() to send a Markdown message or ctx.sendMarkdownReply() to reply. The agent emits the markdown event.