Better than the control, worse than nothing The figure above is measured against the irrelevant-document control. Against no context at all this card is worse: 10% bare against 13% with the best supplied source. What the source repaired is damage the presence of a document did.
~intervals overlap — not separated from no change
Given an injected "current date," the model computes relative dates/intervals incorrectly. The rule
Today is 2026-03-10. What date is 30 days from today? Answer with the full date.
No contextPASS
30 days from 2026-03-10 is **2026-04-09**.
detector fmi_7_3_v1: date arithmetic correct
General contextPASS
2026-04-09
detector fmi_7_3_v1: date arithmetic correct
loop 2026-09-09 · google/gemini-2.5-flash-lite as served · closed weights · released 2025-07 · set s1.4-live · cases v1.7 · conditions v1.0 · ground truth as of 2026-08-09
From no context to real context
5 repeats per case
whiskers are 95% intervals · each step is measured from the stop before it, not from zero
Try the other contexts
stored · no model call
1Questionheld fixed
Today is 2026-01-30. What date is 30 days from today? Answer with the full date.
expected as of 2026-08-09
From 2026-01-30, 30 days later is 2026-03-01 (1 March 2026). Crossing February in a non-leap year.
2Contextchange me
Nothing supplied. The baseline.
3ResponseNo context
No exhibit stored for this context. The full probe log lives outside the repository.
The scoring
Failure rate by context
No context10%[2%–39%] n=40 · eff 11
Irrelevant context3%[0%–30%] n=40 · eff 11
General context13%[3%–42%] n=40 · eff 11
Curated context18%[5%–47%] n=40 · eff 11
0–60% · whisker = 95% interval
Trap vs answerable
No contexttrap 16%answerable 0%
Irrelevant contexttrap 4%answerable 0%
General contexttrap 20%answerable 0%
Curated contexttrap 28%answerable 0%
never pooled · a trap ratio would skew the delta
Residual — what survives
Supplying context did not reduce this failure, it increased it: 10% with no context against 18% under the strongest supplied source. What survives is therefore not a remainder but a substitution — the failures under context are 5 probes the detector still rejected, dominated by: expected 2028-03-01.
Mitigations from the index — the claim
—date libraries via tools
—explicit date arithmetic
fmi_7_3_v1 · 5 repeats per case · best context general context · rollups + residuals committed · probe log outside git · manifest hash ties them · method