Axle Block Restore developer reference

Scripts

There is no build step. The scripts use the wp.* globals WordPress already loads. They load in the post editor for post types with revisions, and in the Site Editor for templates, template parts, synced patterns and anything else that has revisions.

Script	Job
assets/js/matching.js	Block text, similarity ranking, classification, word diff, revision search, attribute roles, partial restores, the inner block comparison, and the removed blocks list with the position a block goes back to. No WordPress dependency, so it is unit tested in Node
assets/js/components.js	The restore window, built on wp.components and wp.blockEditor, and the lookup of which entity a block belongs to
assets/js/index.js	The two menu entries (BlockSettingsMenuControls and PluginMoreMenuItem) and the command palette entries

The window uses core components only (Modal, Card, PanelBody, Button, Notice, Spinner, Badge). assets/editor.css holds layout and nothing else.

More on hooks

// No restoring for reusable blocks, and log every restore.
wp.hooks.addFilter( 'axleBlockRestore.canRestore', 'my-plugin', ( canRestore, block ) => canRestore && 'core/block' !== block.name );
wp.hooks.addAction( 'axleBlockRestore.restored', 'my-plugin', ( details ) => console.log( 'Restored', details.block.name, 'from revision', details.revisionId ) );

// Treat a custom block's "heading" attribute as content, and a "variant" attribute as style.
wp.hooks.addFilter( 'axleBlockRestore.attributeRole', 'my-plugin', ( role, name, blockName ) => {
	if ( 'my/card' !== blockName ) {
		return role;
	}
	return 'heading' === name ? 'content' : 'variant' === name ? 'style' : role;
} );

// Templates and parts only for people who can manage options, and no support for patterns in the Site Editor.
add_filter( 'axle_block_restore_site_editor_post_types', static fn( array $types ) => array_diff( $types, array( 'wp_block' ) ) );
add_filter( 'axle_block_restore_capability', static fn( string $cap, string $type ) => in_array( $type, array( 'wp_template', 'wp_template_part' ), true ) ? 'manage_options' : $cap, 10, 2 );

Load that script with wp-hooks as a dependency, on enqueue_block_editor_assets.

More on abilities

On WordPress 6.9 and later, Axle Block Restore registers abilities, which AI agents find and run through the MCP adapter and anything else through the REST API under /wp-abilities/v1/. Each one is marked public, which the MCP adapter needs before it lists an ability.

Abilities work with post IDs, so they reach templates, template parts and patterns by the ID of their post. Restoring only the content or only the styling is an editor feature: the saved markup of a block (its classes and inline styles) only comes from the block’s own save() function, which runs in JavaScript.

In the editor the plugin guesses which old block matches which current one. An agent does not need the guess: it finds text that was deleted or changed, then names the exact block to bring back. A path counts blocks from 0, one number per level: [2] is the third top-level block, [2, 0] the first block inside it.

All four need edit_post on the post, in a post type that has Axle Block Restore. The find abilities look through 20 revisions by default, 50 at most (axle_block_restore_max_revisions).

Hook	Type	Use
axle_block_restore_restored	action	( int $post_id, array $block, int $revision_id, string $mode ). A block was saved back through restore-block
axle_block_restore_max_revisions	filter	( int $max ). Most revisions the find abilities look through. Default 50

REST

Revisions are fetched 50 at a time from /wp/v2/<rest base>/<id>/revisions with context=edit and _fields=id,wp_id,modified,date_gmt,slug,content.raw,axle_block_restore_author, so the server returns raw block markup and never renders the content. The rest base is templates, template-parts or blocks in the Site Editor.

Template and template part revisions come from core’s templates controller, so each one has id set to the template’s ID (theme//slug), its own ID in wp_id, and its time in modified, in the site’s time zone. The window reads those.

The plugin adds one read-only route, /axle-block-restore/v1/posts (see Copying a block from another post), and one read-only field to revision responses:

Field	Value
axle_block_restore_author	Display name of the revision’s author. Editors cannot always list users, so the name comes with the revision

Data

Nothing is stored. Restores are normal editor changes, saved when the post is updated.