Flutter Skill vs ONCE

In-depth architectural comparison of the Flutter Skill and ONCE MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

Which MCP Server Should You Choose?

Choose Flutter Skill when:

• You need dedicated capabilities in the Developer Tools domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).

Explore Flutter Skill Details

O

Choose ONCE when:

• You need dedicated capabilities in the Developer Tools domain.
• You prefer remote streaming HTTP/SSE transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).

Explore ONCE Details

Feature & Specification Comparison

Specification	Flutter Skill Developer Tools	O ONCE Developer Tools
Summary	AI E2E testing bridge — give AI eyes and hands inside any app. 8 platforms, 40+ tools.	Stop duplicate AI-agent side effects with idempotency, postcondition checks, and durable receipts.
Category & Scope	Developer Tools	Developer Tools
Quality signal

Tools & Capabilities Breakdown

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

{
  "mcpServers": {
    "flutter-skill": {
      "command": "npx",
      "args": [
        "-y",
        "skills"
      ]
    }
  }
}

{
  "mcpServers": {
    "once-2": {
      "url": "https://optimistic-compassion-production.up.railway.app/v1/demo"
    }
  }
}

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