Artifact: Autocomplete vs. Agent Session Tool-Call Log

Autocomplete (single-shot, no tool use)
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Editor cursor sits inside calculator.py, at the end of an empty function body.
Autocomplete suggests, in one shot, with no tool call:
    return a + b
The suggestion is accepted or rejected. Nothing else happens -- no other file
is read, no test is run, no command executes.
 
Agent session (multiple tool invocations)
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Task given: "add input validation to add_positive() and cover it with a test."
1. read_file(path="calculator.py")
2. edit_file(path="calculator.py",
              diff="+  if a < 0 or b < 0:\n+      raise ValueError('inputs must be non-negative')")
3. edit_file(path="tests/test_calculator.py",
              diff="+  def test_add_positive_rejects_negative():\n+      with pytest.raises(ValueError):\n+          add_positive(-1, 2)")
4. run_shell(command="pytest tests/test_calculator.py -q")
5. read_file(path="pytest output")   # => reads back "1 passed" before considering the task done