To make your custom node appear in the AI Panel, you need to add `usableAsTool: true` to your node’s configuration and set the environment variable `N8N_COMMUNITY_PACKAGES_ALLOW_TOOL_USAGE=true` as mentioned in the [github.com](Custom Node as an AI tool · Issue #12593 · n8n-io/n8n · GitHub) issue.
For creating grouped actions like Anthropic/OpenAI, you’ll need to structure your custom node as a cluster node with a root node and sub-nodes. Check the [community.n8n.io](Custom AI Tool) discussion where users explain that the TypeScript definitions might not include `usableAsTool` yet, so you may need to use `//@ts-ignore` to compile.
The AI Panel specifically looks for nodes with the proper AI tool configuration - simply adding “Root Nodes” to the AI subcategory won’t be enough without the `usableAsTool` property and proper cluster node structure.