Executing summarization ability with @wordpress/abilities in WordPress 7.0 doesn't work due to invalid schema

[ocean90]

Description

I was testing the changes mentioned in https://make.wordpress.org/core/2026/03/24/client-side-abilities-api-in-wordpress-7-0/ with the summarization ability but couldn't get it executed.

Step-by-step reproduction instructions

Example snippet:

/**
 * Generates an AI summary for our review text using the WordPress Abilities API.
 *
 * The Abilities API is a Script Module (`@wordpress/abilities`), so it must be
 * loaded via dynamic `import()` from classic scripts. Server-registered abilities
 * (like `ai/summarization`) are available when `@wordpress/core-abilities` is
 * enqueued, which WP 7.0 does on all admin pages.
 *
 * Falls back to `null` when the Abilities API or the ai/summarization ability
 * is not available.
 *
 * @param text The review text to summarize.
 * @return The generated summary, or null on failure.
 */
export async function generateSummary(
	text: string
): Promise< string | null > {
	try {
		const { executeAbility } = await import(
			/* webpackIgnore: true */ '@wordpress/abilities'
		);

		const result = await executeAbility( 'ai/summarization', {
			content: text,
			length: 'medium',
		} );
		return typeof result === 'string' && result.length > 0
			? result
			: null;
	} catch ( error ) {
		console.error( 'Error generating AI summary:', error );
		return null;
	}
}

The first error:

Schema compilation error: Error: schema is invalid: data/properties/length/type must be equal to one of the allowed values, data/properties/length/type must be array, data/properties/length/type must match a schema in anyOf
Error generating AI summary: Error: Ability "ai/summarization" has invalid input. Reason: Invalid schema provided for validation.

After fixing the type in I got another one:

Schema compilation error: Error: strict mode: unknown keyword: "sanitize_callback"
Error generating AI summary: Error: Ability "ai/summarization" has invalid input. Reason: Invalid schema provided for validation.

This one I'm not sure how to fix.

Screenshots, screen recording, code snippet

No response

Environment info

• WordPress 7.0 RC
• AI 0.6.0

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except the AI plugin.

• Yes

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure

[ocean90]

@dkotter Could you please reopen this issue? The second part about sanitize_callback isn't fixed yet.

/cc @jorgefilipecosta

[dkotter]

@dkotter Could you please reopen this issue? The second part about sanitize_callback isn't fixed yet.

/cc @jorgefilipecosta

Note I ran into this myself yesterday while working to update our client-side handling to use the new API. Seems sanitize_callback is not supported for schemas so we'll need to remove that and add our own sanitization. Should have a PR open today that resolves this

[dkotter]

@ocean90 Opened #364 that I think fixes all issues, or at least I'm not running into any more when using the client-side API. If you have time to test that out, that would be great

[jorgefilipecosta]

Hi @ocean90, @dkotter thank you for looking into this. I think this is a core issue and we may need need changes on the AI plugins. These WordPress specific keywords don't add any value, on the client so they should be removed. I'm doing that at WordPress/gutenberg#77029 and it seems to fix the issue. Appreciate any feedback there.

I think they should also be removed before being passed to any LLM as they just consume tokes there e.g: on using_abilities on WP AI Client, or on the MCP adapter but that is a different problem we may look into.