MCP Mode
MCP Mode turns Atom into an MCP server that external AI agents can connect to. Instead of chatting inside the panel, you use agents like Claude Code or Codex to control After Effects through Atom's tools.
The Atom panel must stay open in After Effects while MCP Mode is active. It serves as the bridge between your external agent and After Effects.
Enabling MCP Mode
Open Settings and scroll to the MCP section. You will see toggles for supported agents and a URL option for other clients.
- Claude — Toggle on to register Atom as an MCP server with Claude Code automatically
- Codex — Toggle on to register with OpenAI Codex CLI automatically
- URL — Toggle on to get a raw URL you can copy into any MCP-compatible client
Toggling any of these on starts the MCP server and switches the panel to the connector overlay.
When you toggle Claude or Codex on, Atom runs the registration command for you. There is no manual configuration needed if the agent CLI is installed on your machine.
Port Configuration
By default, Atom picks an open port automatically. You can also set a fixed port in the Port field. The port must be between 1024 and 65535. Click Find Open Port to let Atom scan for an available one.
If you set a fixed port and it is already in use, Atom will show an error and ask you to choose another.
Connecting Manually
If your agent is not listed in the settings toggles, use the URL toggle to start the server and copy the URL. The URL format is:
http://127.0.0.1:{port}/mcp You can then register this URL with any MCP-compatible client following that client’s own documentation.
The MCP server only accepts local connections (127.0.0.1). It is not accessible from other machines on your network.
Switching Back to Chat Mode
To return to the normal chat interface, open Settings and turn off all the MCP toggles (Claude, Codex, and URL). Atom will stop the MCP server and switch back to the chat view.
You can switch between modes at any time without losing your settings or skills.
If you have an active chat session running, switching to MCP Mode will stop the current agent. Atom will ask for confirmation before switching.