Failure path

Every team ends with re-verifier. When it finds a difference, the team stops before landing and goes back to the agent that can explain the difference, then ports and verifies again. This page shows where a failure goes.

What differs	Agent	What it does
A value or a picture	re-tracer	Re-reads the function at the first difference
The order of random draws	re-randomiser	Finds the extra or missing draw
Arithmetic in the last bit	re-measurer	Measures the step that differs
A file's bytes	re-decoder	Finds the field that differs
A run differs from itself	re-listener	Finds the input that is not in the record

What the verifier hands on

A failing hand-off names the first difference:

## Hand-off
Stage: re-verifier
Done: compared 600 values; 412 identical
Evidence: derived/verify/terrain-diff.txt
Open: first difference at input 413, field height, 0.5 ULP
Next: re-measurer - measure FUN_140041a20 at input 413, step by step

Rules for the main session

• Send the agent the table above points to, with the first difference in its brief.
• Three rounds on the same difference without progress is a signal to stop. Write down what was tried in docs/CHECKLIST.md and ask the user.
• A run that differs from itself points to something outside the input record that reaches the rules: a clock, an uninitialised value, iteration over a hash map. Send re-listener.
• Never land a slice with a known difference unless the user agrees to record it as a deviation.