build_call_path summed the out-degree of every reached function, so a terminal goal's callees counted as explored even though the forward search never expands the goal. Count explored edges and depth at the expansion boundary inside the search, drop the post-hoc summary and the now-unused out-degree helper, and reuse the schema-owned explored type. Fixes #5906 Co-authored-by: Claude Opus 5.5 <[email protected]>