How do I install once?

Pick a client above and copy the generated config. Cursor and VS Code also have a deep link when the server can run locally or remotely.

No. Registry-listed is not the same as vendor-official. Read the methodology for the difference.

How is the trust score calculated?

This listing scores 55 (Fair). The formula is published on the methodology page.

MCPpedia

once MCP Server

Name: once MCP Server
Author: stringsofthemind-oss

Developer assessment/setup MCP; admitted Once boundaries protect writes, not sibling connectors.

Tools Versions Alternatives

Registrystringsofthemind-oss

55Fair

Install

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "stringsofthemind-oss-once": {
      "command": "npx",
      "args": [
        "-y",
        "@once-agent/mcp@0.2.1"
      ],
      "env": {
        "ONCE_API_KEY": "YOUR_ONCE_API_KEY"
      }
    }
  }
}

Install guide

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Name	Required	Notes
ONCE_API_KEY	No	Optional key for Cloud checks. Without it once_verify_connection reports Cloud unconfigured/unverified and preserves local diagnostics. Secret.

once MCP Server — Install for Claude, Cursor & VS Code | MCPpedia

once MCP Server

Install

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