>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3527412. --> Reported by: [jurgenhaas](https://www.drupal.org/user/168924) Related to !514 >>> <h3 id="summary-problem-motivation">Problem/Motivation</h3> <p>We had considered exposing all ECA action plugins to AI, especially to agents and to MCP, but it turns out that for 2 reasons that's not a valid approach:</p> <ul> <li>The action plugins are far too granular</li> <li>They are missing metadata that would be necessary for agents and MCP to make use of them</li> </ul> <p>Instead, let's expose custom events. They are the starting point for small or large models that provide some functionality, taking specified input and provide their result as structured output.</p> <h3 id="summary-proposed-resolution">Proposed resolution</h3> <p>Let's enhance the custom event configuration such that the user can optionally provide extra metadata like input specification, description, etc., and then provide a plugin deriver to expose that custom event as a plugin implementing <code>\Drupal\ai\Service\FunctionCalling\ExecutableFunctionCallInterface</code>.</p>