Measures three overlay bullets that haven't been tested yet:
- claude-dedicated-tools-vs-bash — claude.md says 'prefer Read/Edit/Write/
Glob/Grep over cat/sed/find/grep'. Fixture prompts 'list every TypeScript
file under src/ and tell me what each exports' and counts Bash tool_use
across the session. Overlay-ON should drop it by >=20%.
- opus-4-7-effort-match-trivial — opus-4-7.md says 'simple file reads
don't need deep reasoning.' Fixture uses a trivial one-file prompt
(config.json lookup) and measures turns_used. Overlay-ON should be
<=80% of baseline turns.
- opus-4-7-literal-interpretation — opus-4-7.md says 'fix ALL failing
tests, not just the obvious one.' Fixture seeds three failing test
files with deliberately distinct failure modes and counts unique files
edited. Overlay-ON should touch >=20% more files.
Adding a fourth fixture for any remaining overlay nudge is a single entry.
The harness is now proven on: fanout (deleted after measurement), dedicated
tools, effort-match, and literal-interpretation.
Garry Tan
04e2f1bea9