Parameters

A bash tool definition has two required fields, type and name, and the name must be bash. The tool is schema-less: you don't provide an input_schema, because the schema is built into Claude's model and can't be modified. The following table lists the input fields Claude sets when it calls the tool.

Parameter	Required	Description
command	Yes*	The bash command to run
restart	No	Set to true to restart the bash session

*Required unless using restart

To handle restart: true, kill the shell process, start a new one, and return a tool_result that confirms the restart. A restarted session starts clean: the working directory, environment variables, and any running processes are gone.

Run a command:

{
  "command": "ls -la *.py"
}

Restart the session:

{
  "restart": true
}