google/python-fire · error · ValueError

Cannot make completion script without command name

Error message

Cannot make completion script without command name

What it means

Requesting a completion script (-- --completion [shell]) requires knowing the installed command name so the generated script can hook into it. If fire.Fire() is called without the `name` parameter while completion is requested, this ValueError is raised.

Source

Thrown at fire/core.py:599

      elif component is not last_component:
        remaining_args = [separator] + saved_args
      else:
        # It was an unnecessary separator.
        remaining_args = saved_args

    if component is last_component and remaining_args == initial_args:
      # We're making no progress.
      break

  if remaining_args:
    component_trace.AddError(
        FireError('Could not consume arguments:', remaining_args),
        initial_args)
    return component_trace

  if show_completion is not None:
    if name is None:
      raise ValueError('Cannot make completion script without command name')
    script = CompletionScript(name, initial_component, shell=show_completion)
    component_trace.AddCompletionScript(script)

  if interactive:
    variables = context.copy()

    if name is not None:
      variables[name] = initial_component
    variables['component'] = initial_component
    variables['result'] = component
    variables['trace'] = component_trace

    if instance is not None:
      variables['self'] = instance

    interact.Embed(variables, verbose)

    component_trace.AddInteractiveMode()

View on GitHub (pinned to 716bbc23d7)

Solutions

1. Pass the command name: fire.Fire(component, name='mytool')
2. Use fire.Fire(component=component, name=str(sys.argv[0])) or the module name in the entry point
3. Avoid -- --completion when no name is provided

Example fix

// before
fire.Fire(component)  # user runs: mytool -- --completion bash
// after
fire.Fire(component, name='mytool')

if show_completion and name is None:
    raise ValueError('pass name= to fire.Fire to enable --completion')

try:
    fire.Fire(component, name=name)
except ValueError as e:
    if 'completion script' in str(e):
        sys.exit('completion requires name=')
    raise

When it happens

Trigger: Running `mytool -- --completion bash` when the entry was fire.Fire(component) with no name= argument; calling fire.Fire(component, show_completion='bash') programmatically with name=None.

Common situations: Tools installed via console_scripts that forgot to pass name=__file__ or the command name; tests invoking Fire without a name but exercising completion.

Understand the failure class

Background: Missing required parameter errors: what 'X is required' and 'the required X param is missing' mean, and how to fix them — this error's family across 27 libraries.

Related errors

• Given file path does not exist.
• Unable to load module from specified path.
• Fire can only be called on .py files.
• Fire was passed a filename which could not be found.
• The command argument must be a string or a sequence of argum

AI-assisted analysis of google/python-fire@716bbc23d7 (2026-08-28). Data as JSON: /api/errors/a5a36f83facdcfef. Report an issue: GitHub.