LH MCP Block Transformer

LH MCP Block Transformer converts content between HTML, Markdown and native Gutenberg block markup, in both directions, and exposes that conversion as MCP abilities. Its purpose is to let AI-authored content land in WordPress as real, editable blocks rather than as an opaque lump of HTML that an editor cannot meaningfully work with afterwards.

The conversion itself is done by automattic/blocks-engine-php-transformer. This plugin is the WordPress and MCP surface around it: ability registration, capability checks, a pattern guide describing what the transformer recognises, and a save path that never requires block markup to be transcribed by hand.

Key features

• HTML or Markdown to Gutenberg blocks, with diagnostics reporting anything that fell back to a generic wrapper.
• The reverse conversion, for reading an existing block-based post into an editable format and converting it back without losing block structure.
• Convert and save an existing post in one server-side step, taking only post IDs, so converted markup never round-trips through the caller.
• A pattern guide describing which HTML and CSS shapes reliably produce the richer blocks, so content can be authored to hit them deliberately.

Install and setup

Activate the plugin, then run composer install in its directory to fetch the transformer library. This must be repeated after any WordPress zip install, which wipes the vendor directory. If the library is missing, the abilities return a clear error rather than failing silently or fatally.

No configuration is required. Abilities are available to any caller holding the edit_posts capability.

Contents

• Abilities
• Architecture notes
• Changelog