Example. A short code-agent trace with tool evidence [ftip-004V]

A failing test observation triggers a second edit, whose passing tool evidence determines the terminal result.

The public history records both edits and both test outputs. The first tool call returns the evidence string expected 9, got 6; the second returns exit status \(0\) and 1 passed. The success rule reads the second test result rather than the model's assertion that its edit is correct.

The action--observation alternation follows the tool-interleaving pattern in [yao2023react, Section 2]. The transparent sandbox interaction certifies only the displayed test result; completeness of the suite and satisfaction of unstated intent remain unverified.