A2ui Validate

Developer MCP

Validates a JSONL A2UI payload against the basic catalog (or a custom catalog) and returns any errors, warnings, or info messages with exact line numbers. Call this on every LLM-generated payload before sending to the client.

This page documents the MCP tool findutils:a2ui_validate.

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Call it over MCP

Tool name findutils:a2ui_validate · no API keys · 120 requests/min per IP

Claude Code

claude mcp add findutils --transport http https://mcp.findutils.com/

Claude Desktop — claude_desktop_config.json

{
  "mcpServers": {
    "findutils": {
      "url": "https://mcp.findutils.com/"
    }
  }
}

Raw JSON-RPC (any MCP client) — verified example

curl -X POST https://mcp.findutils.com/ \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "a2ui_validate",
      "arguments": {
        "payload": "{\"version\":\"v0.9\",\"createSurface\":{\"surfaceId\":\"s\",\"catalogId\":\"x\"}}"
      }
    }
  }'

Input schema

Fetch this tool's machine-readable schema from GET https://api.findutils.com/api/tools/, or call tools/list on the MCP server.

Example arguments (verified)

{
  "payload": {
    "version": "v0.9",
    "createSurface": {
      "surfaceId": "s",
      "catalogId": "x"
    }
  }
}

Arguments that carry JSON as a string are shown decoded for readability. The Copy button copies the exact wire arguments.

More Developer tools

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