Use Thrum with Antigravity

Free and Pro

With the Thrum plugin installed in Antigravity, you can ask your coordinator to put an agent on Antigravity, Google’s command-line coding agent (agy). Your coordinator is the agent you talk to, which starts the other agents, hands out work and reports back to you. That agent reads messages from the same inbox as your Claude Code agents, so you can choose the tool for each task and still work from one place.

Thrum has no separate Antigravity plugin. Antigravity installs Thrum’s Claude Code plugin and converts it to its own format. The agent keeps the plugin’s skills, commands and agent, but not its hooks. The quickstart starts your coordinator on Claude Code. This plugin matters for the agents the coordinator creates on Antigravity.

What the plugin gives you

Thrum’s skills and commands inside Antigravity. The conversion keeps the plugin’s skills and its commands. Commands include sending a message and reading the inbox.
The plugin’s agent. The conversion keeps the agent that comes with the plugin.
A briefing at the start of every Antigravity session. A briefing is a short summary of who the agent is, where the project stands and what it has been sent. Antigravity does not run the plugin’s hooks, which are scripts that other tools run by themselves at a set moment, such as when a session starts. So Thrum types /thrum:prime, the command that loads the briefing, into the agent’s session itself when it starts the agent. If you start an agy session yourself, type /thrum:prime there.
No MCP server by default. The conversion skips MCP. If you want the MCP server, ask your coordinator: Add the Thrum MCP server to Antigravity.

Before you start

Antigravity’s command-line tool, agy. agy updates itself.
Thrum set up in your repository, with a running coordinator. The quickstart starts one on Claude Code. That is the recommended way to begin, and the steps on this page assume it.

Add Antigravity agents through your coordinator

Ask your coordinator (in its terminal, or in My Inbox, your inbox in Thrum’s web UI):

Install the Thrum plugin for Antigravity.

It installs the plugin from the claude-plugin folder of thrum-team/thrum-pro, the repository the plugin is distributed from.
Check that the plugin is installed. Ask your coordinator: Is the Thrum plugin installed in Antigravity? The answer should say thrum is enabled.
Ask your coordinator for an Antigravity agent. Say “on Antigravity” in your message. The runtime name is antigravity, and agy also works. A runtime is the AI coding tool an agent runs in, such as Claude Code or Codex. This is an example conversation. Your coordinator’s wording will differ.
```
You:
  Create an agent on Antigravity to review the README. Give it its own worktree.

Coordinator:
  Created reviewer_readme in a new worktree and sent it the task. I'll tell you when it replies.
```
The New Agent dialog in the web UI has no runtime field and always creates Claude Code agents. For Antigravity, ask the coordinator.
Check it worked. On the Agents grid, a card for the new agent appears. Open it, then its Terminal tab, which shows the Antigravity agent’s own screen. You see /thrum:prime run, then one line that names the agent:
```
@reviewer_readme primed (reviewer/main). Reviewing README.md. Standing by.
```

If your coordinator will run in Antigravity

Skip this section if your coordinator runs in Claude Code. If Antigravity will be your first agent, there is no coordinator to ask yet, so install the plugin yourself with this command. thrum-team/thrum-pro is where the plugin is distributed from. It holds the plugin’s text files, not the Thrum program. Free and Pro both use this same plugin. Thrum is published by THRUM LLC and built by Leon Letto (About).

agy plugin install https://github.com/thrum-team/thrum-pro/tree/main/claude-plugin

To check it, run agy plugin list. thrum must show as enabled.

Tips

To update the plugin, ask your coordinator to run the install again: Run the Thrum plugin install for Antigravity again, then reload the skills in every running Antigravity agent. After an update, each running Antigravity session needs /skills reload. It does not need a restart. Your coordinator can type the command into each agent’s terminal for you.
Do not use agy plugin validate to check the install. It checks only Antigravity’s own plugin format, and the Thrum plugin is a Claude Code plugin that the install step converts, so validate reports a failure that does not mean the install is broken. Use agy plugin list instead.
Thrum starts agy with an effort level: medium, unless you ask your coordinator for another. It does not choose a model, so agy uses its own default model unless you ask your coordinator for one.
Most commands run without a prompt. Thrum writes two lists into Antigravity’s settings file, ~/.gemini/antigravity-cli/settings.json: commands that may run without asking, and commands that may not. Some commands, such as ones that use a > redirect, still ask, and those prompts show in the agent’s Terminal tab. If Antigravity asks “Do you trust the contents of this project?”, Thrum answers for you.
When an Antigravity agent’s conversation fills its window and is compacted (shrunk), Thrum does not reload its briefing. When the agent’s context is nearly full, Thrum reminds it to restart. After a restart, Thrum types /thrum:prime again, so the agent gets its briefing back. Mix runtimes and models has more on how runtimes differ.

Next steps

Mix runtimes and models: choose the tool and model for each task.
Messaging between agents: how the coordinator and an Antigravity agent talk.
Use Thrum with Muse: the same idea for Muse.