> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mem0.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Antigravity

> Add persistent memory to Google Antigravity with the Mem0 plugin: MCP server, lifecycle hooks, and slash commands.

Add persistent memory to [**Google Antigravity**](https://antigravity.google) (`agy` CLI and Desktop IDE) with the Mem0 plugin. Your agent forgets everything between sessions. Mem0 fixes that by storing decisions, preferences, and learnings so they carry over automatically.

## Prerequisites

1. A Mem0 API key (starts with `m0-`):
   * <a href="https://app.mem0.ai/dashboard/api-keys?utm_source=oss&utm_medium=integration-antigravity" rel="nofollow">Get your API key</a> (free sign-up at <a href="https://app.mem0.ai?utm_source=oss&utm_medium=integration-antigravity" rel="nofollow">app.mem0.ai</a>)

2. Add it to your shell profile so it persists across sessions:

<CodeGroup>
  ```bash zsh theme={null}
  echo 'export MEM0_API_KEY="m0-your-api-key"' >> ~/.zshrc && source ~/.zshrc
  ```

  ```bash bash theme={null}
  echo 'export MEM0_API_KEY="m0-your-api-key"' >> ~/.bashrc && source ~/.bashrc
  ```
</CodeGroup>

## Installation

**Option A: degit** (recommended):

```bash theme={null}
# Install the plugin (MCP server, hooks, scripts)
npx degit mem0ai/mem0/integrations/mem0-plugin ~/.gemini/config/plugins/mem0
```

This installs the MCP server, lifecycle hooks, and shared scripts.

## What's Included

| Component                   | Included |
| --------------------------- | :------: |
| MCP Server (9 memory tools) |    Yes   |
| Lifecycle Hooks             |    Yes   |
| 16 Slash Commands           |    Yes   |

## Available MCP Tools

| Tool                  | Description                                         |
| --------------------- | --------------------------------------------------- |
| `add_memory`          | Save text or conversation history for a user/agent  |
| `search_memories`     | Semantic search across memories with filters        |
| `get_memories`        | List memories with filters and pagination           |
| `get_memory`          | Retrieve a specific memory by ID                    |
| `update_memory`       | Overwrite a memory's text by ID                     |
| `delete_memory`       | Delete a single memory by ID                        |
| `delete_all_memories` | Bulk delete all memories in scope                   |
| `delete_entities`     | Delete a user/agent/app/run entity and its memories |
| `list_entities`       | List users/agents/apps/runs stored in Mem0          |

## Lifecycle Hooks

The plugin uses the same shell scripts as Claude Code, Cursor, and Codex: hooks bridge environment variables using `${extensionPath}` (Antigravity's plugin-root token).

| Hook              | Event              | What it does                                                       |
| ----------------- | ------------------ | ------------------------------------------------------------------ |
| **Session start** | `SessionStart`     | Loads prior memories and displays status banner                    |
| **User prompt**   | `UserPromptSubmit` | Searches relevant memories before each message                     |
| **Pre-tool**      | `PreToolUse`       | Blocks MEMORY.md writes, enforces `user_id`/`app_id` on mem0 tools |
| **Post-tool**     | `PostToolUse`      | Tracks stats, scans bash errors for related memories               |
| **Stop**          | `Stop`             | Stores a session summary when the session ends                     |

## Troubleshooting

* **No tools appearing**: Restart your Antigravity session after installation
* **"Connection failed"**: Verify your key is set: `echo $MEM0_API_KEY`
* **MCP 401 Unauthorized**: If `${MEM0_API_KEY}` interpolation doesn't work in your `agy` version, replace with your literal key in `mcp_config.json`

<CardGroup cols={2}>
  <Card title="Mem0 MCP Setup" icon="puzzle-piece" href="/platform/mem0-mcp">
    Detailed MCP configuration for all clients
  </Card>

  <Card title="OpenCode Integration" icon="code" href="/integrations/opencode">
    Add Mem0 memory to OpenCode workflows
  </Card>
</CardGroup>

<Snippet file="star-on-github.mdx" />