@mcp-packages/flagsmith-server

MCP server for Flagsmith — list, search, inspect, and toggle feature flags via the Model Context Protocol.

Designed for self-hosted Flagsmith instances. Connects to the Flagsmith Admin API over VPN.

Setup

1. Create an API Token

1. Log in to your Flagsmith dashboard
2. Go to Organisation Settings → API Keys
3. Create an Admin API token
4. Note your Project ID (visible in the dashboard URL: /project/<id>/...)

2. Environment Variables

| Variable | Required | Description | |---|---|---| | FLAGSMITH_API_TOKEN | Yes | Admin API token for authentication | | FLAGSMITH_BASE_URL | Yes | Base URL of your Flagsmith API (e.g., https://flagsmith.yourcompany.com/api/v1) | | FLAGSMITH_PROJECT_ID | Yes | Numeric project ID |

3. Configure Your IDE

Cursor (.cursor/mcp.json)

{
  "mcpServers": {
    "flagsmith": {
      "command": "npx",
      "args": ["-y", "@mcp-packages/flagsmith-server"],
      "env": {
        "FLAGSMITH_API_TOKEN": "${FLAGSMITH_API_TOKEN}",
        "FLAGSMITH_BASE_URL": "https://flagsmith.yourcompany.com/api/v1",
        "FLAGSMITH_PROJECT_ID": "12345"
      }
    }
  }
}

Claude Code

claude mcp add flagsmith -- npx -y @mcp-packages/flagsmith-server

Set environment variables in your shell profile (~/.zshrc):

export FLAGSMITH_API_TOKEN="your-token"
export FLAGSMITH_BASE_URL="https://flagsmith.yourcompany.com/api/v1"
export FLAGSMITH_PROJECT_ID="12345"

Tools

| Tool | Description | |---|---| | list_flags | List all feature flags in the project | | search_flags | Search flags by name substring | | get_flag | Get flag details including state across all environments | | get_environment_flags | Get all flag states for a specific environment | | toggle_flag | Enable or disable a flag in an environment | | update_flag_value | Update a flag's remote config value in an environment |

Tool Details

list_flags

No parameters. Returns all flags with name, description, tags, default enabled state, and type.

search_flags

| Parameter | Type | Required | Description | |---|---|---|---| | query | string | Yes | Search term to match against flag names |

get_flag

| Parameter | Type | Required | Description | |---|---|---|---| | flagName | string | Yes | Exact name of the feature flag |

Returns flag metadata plus enabled state and value for every environment.

get_environment_flags

| Parameter | Type | Required | Description | |---|---|---|---| | environmentKey | string | Yes | Flagsmith environment API key (e.g., ser.abc123...) |

toggle_flag

| Parameter | Type | Required | Description | |---|---|---|---| | flagName | string | Yes | Exact name of the feature flag | | environmentKey | string | Yes | Flagsmith environment API key | | enabled | boolean | Yes | true to enable, false to disable |

update_flag_value

| Parameter | Type | Required | Description | |---|---|---|---| | flagName | string | Yes | Exact name of the feature flag | | environmentKey | string | Yes | Flagsmith environment API key | | value | string | Yes | New remote config value (plain string or JSON) |

Development

# Install dependencies (from monorepo root)
npm install

# Build
npm run build -w @mcp-packages/flagsmith-server

# Watch mode
npm run dev -w @mcp-packages/flagsmith-server