--- title: Antigravity description: "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-`): - Get your API key (free sign-up at app.mem0.ai) 2. Add it to your shell profile so it persists across sessions: ```bash zsh echo 'export MEM0_API_KEY="m0-your-api-key"' >> ~/.zshrc && source ~/.zshrc ``` ```bash bash echo 'export MEM0_API_KEY="m0-your-api-key"' >> ~/.bashrc && source ~/.bashrc ``` ## Installation **Option A: degit** (recommended): ```bash # 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` Detailed MCP configuration for all clients Add Mem0 memory to OpenCode workflows