Function Calling Schema Builder

Turn a function outline into a JSON schema.

Runs in your browser. Nothing is uploaded — your input is processed on this device and discarded when you close the tab.

Function Calling Schema Builder

How to use this tool

  1. Enter the function name and a short description.
  2. List each parameter on its own line as name:type:yes for required or name:type:no for optional.
  3. Press Generate for the JSON schema to copy into your own code.

Worked example

For the function getWeather, described as "Get current weather for a city", with the parameter city:string:yes, the schema has a properties object with city of type string and a required list containing city.

What this tool does not do / Limits

This tool builds a basic schema with type and required fields only. It does not support nested objects, enums, or validation against any model, and it does not call any service.

Frequently asked questions

Which types can I use?

Any short type word, such as string, number, boolean or integer. The tool copies the word you type; it does not check it against a schema standard.

What if a line has no type?

Lines without a colon-separated type are skipped, since the tool cannot tell what type that parameter should be.

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