# Assertion Memory MCP server

> Provides coding agents with a shared project memory to recall decision logic and strategy across Claude Code, OpenAI Codex, and Cursor.

- Repository: https://github.com/Assertion-AI/assertion
- Page: https://hostedmcp.org/servers/assertion-ai/assertion
- Transport: remote
- Stars: 1
- License: Apache-2.0
- Latest version: 1.0.0

## Install

### Claude Code

```sh
claude mcp add --transport http assertion https://memory.assertion-ai.com/memory/mcp
```

### Cursor (`~/.cursor/mcp.json`)

```json
{
  "mcpServers": {
    "assertion": {
      "url": "https://memory.assertion-ai.com/memory/mcp"
    }
  }
}
```

### VS Code (`.vscode/mcp.json`)

```json
{
  "servers": {
    "assertion": {
      "type": "http",
      "url": "https://memory.assertion-ai.com/memory/mcp"
    }
  }
}
```

### Codex (`~/.codex/config.toml`)

```toml
[mcp_servers.assertion]
url = "https://memory.assertion-ai.com/memory/mcp"
```

### Gemini CLI (`~/.gemini/settings.json`)

```json
{
  "mcpServers": {
    "assertion": {
      "httpUrl": "https://memory.assertion-ai.com/memory/mcp"
    }
  }
}
```

## Environment variables

| Name | Required | Secret | Description |
|---|---|---|---|
| `ASSERTION_API_KEY` | no | no |  |

## FAQ

### What does the memory actually store?

The memory stores decisions and the reasoning behind them, rather than raw transcripts or source code.

### How do I sign in to Assertion?

You can sign in via your browser through a command like /assertion:login, or use an ASSERTION_API_KEY for CI or shared machines.

### Does it require any specific dependencies?

It requires a system installation of python3 for the standard library hooks, but no other dependencies are needed.