---
name: agent-add-mcp
description: Use this skill when helping users add MCP servers to their Warp configuration.
---

# Adding MCP Servers to Warp

Warp supports MCP servers via native config files. Follow these steps when helping a user add an MCP server.

## Step 1: Determine Scope

If the user hasn't specified, ask whether they want to configure the server **globally** (for all projects) or **project-scoped** (for a specific repository only).

Config file paths:
- **Global (user-scoped):** `~/.warp/.mcp.json`
- **Project-scoped:** `{repo_root}/.warp/.mcp.json`

## Step 2: Gather Server Details

If the user hasn't provided the server's connection details, use WebSearch to find the correct configuration for the named server.

If it's unclear whether the server should be run as a local CLI process (stdio transport) or connected to via URL (HTTP/SSE streaming transport), ask the user which they prefer.

## Step 3: Check and Prepare the Config File

Check whether the target config file exists.

- **If it does not exist**, create it with `mkdir -p` for the directory and initialize it with an empty `mcpServers` wrapper key:
  ```json
  {
    "mcpServers": {}
  }
  ```

- **If it exists**, read it to determine which top-level wrapper key is already in use. Recognized wrapper keys (in order of preference):
  - `mcpServers` *(preferred)*
  - `mcp_servers`
  - `servers`
  - `mcp.servers` (nested under a `mcp` key)
  - Flat map (each top-level key is a server name)

  Preserve the existing wrapper key when writing. If the existing key is unrecognized or incompatible, switch to `mcpServers`.

  **Never remove existing server entries** — only add or update the new server.

## Step 4: Write the Server Configuration

### Command-based server (stdio transport)

```json
{
  "mcpServers": {
    "server-name": {
      "command": "npx",
      "args": ["-y", "@scope/package-name"],
      "env": {
        "API_KEY": "${API_KEY}"
      }
    }
  }
}
```

By default, Warp spawns stdio servers from the directory the config was discovered in:
- Project-scoped configs (`{repo_root}/.warp/.mcp.json`) run from the repo root.
- Global configs (`~/.warp/.mcp.json`, `~/.claude.json`, etc.) run from the home directory.

If the server's `command` or `args` are relative paths (e.g. `./tooling/mcp/server.js`) or the server expects a specific cwd, set `working_directory` to override the default:

```json
{
  "mcpServers": {
    "server-name": {
      "command": "node",
      "args": ["./tooling/mcp/server.js"],
      "working_directory": "/absolute/path/to/repo"
    }
  }
}
```

### URL-based server (HTTP/SSE streaming transport)

```json
{
  "mcpServers": {
    "server-name": {
      "url": "https://example.com/mcp",
      "env": {
        "API_KEY": "${API_KEY}"
      }
    }
  }
}
```

For environment variables containing secrets, use `${VAR_NAME}` syntax — Warp will substitute the value from the user's environment at runtime.

## Notes

- Warp auto-detects changes to `.mcp.json` files on save — no restart required.
- Configured servers appear in Warp's Settings under MCP, labeled **"Detected from Warp"**.
- Global config applies across all sessions; project config only applies when working inside that repository.