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PKU123: Missing Description Property

Error Message​

[PKU123] MCP [tool|resource|prompt] '[name]' is missing a description.

What Went Wrong​

Your MCP endpoint is missing the required description property. Descriptions help AI assistants understand what your endpoint does and when to use it.

How to Fix​

Add a clear, descriptive description property:

import { addMCPTool } from '@pikku/core/mcp'
import { pikkuFunc } from '#pikku'

addMCPTool({
  name: 'calculateSum',
  description: 'Adds two numbers together and returns the sum', // ✅ Add this
  func: pikkuFunc(async ({ a, b }: { a: number; b: number }) => {
    return { sum: a + b }
  }),
})

Best Practices​

  • Be specific about what the endpoint does
  • Include information about parameters if relevant
  • Keep it concise but informative
  • Use action verbs (e.g., "Calculates...", "Fetches...", "Updates...")

Common Mistakes​

  • Leaving the description field empty
  • Using very generic descriptions like "A tool" or "Does stuff"
  • Omitting the field entirely