ModelCensusopen-source ai reliability harness
The finding · Class 5 · Robustness & Consistency

Real context moved 0.0pp on Paraphrase Non-Invariance.

~intervals overlap — not separated from no change

Meaning-preserving paraphrases of the same question yield materially different answers. The rule

openai/gpt-4o-minifmi_5_25 repeatsfmi_5_2_v1
The modeAll 10 cards
In one frame
screenshot this
Paraphrase Non-Invariancefmi_5_2
openai/gpt-4o-mini
Same question, both times
How many bones are in the adult human body?
No contextPASS

In an adult human, the total number of bones is typically 206. This number can vary slightly due to individual variations, such as the presence of extra small bones called accessory bones or variations in the number of certain bones, like the ribs. However, 206 is the standard count for a typical adult skeleton. In infants, the number of bones is higher (around 270) because some bones fuse together during growth and development.

detector fmi_5_2_v1: answers invariant across paraphrases

General contextPASS

In an adult human, the total bone count is typically 206. However, this number can vary slightly due to individual differences, such as the presence of extra bones (accessory bones) or variations in the fusion of certain bones.

detector fmi_5_2_v1: answers invariant across paraphrases

Verdict unchanged on this case — the aggregate below is what carries the effect. Across 5 repeats: 0.0pp (intervals overlap).fmi_5_2_v1 · openai/gpt-4o-mini · 2026-08-15 · ground truth as of 2026-08-09

loop 2026-08-15 · openai/gpt-4o-mini as served · closed weights · released 2024-07 · set s1.3-live · cases v1.6 · conditions v1.0 · ground truth as of 2026-08-09

From no context to real context
5 repeats per case
failure rate · left is fewer failures0%5%10%15%20%No context0%[0%–11%] n=30Irrelevant context0%presence — a document being there[0%–11%] n=300.0pp OVERLAPSGeneral context0%content — the information itself[0%–11%] n=300.0pp OVERLAPS
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
How many bones are in the adult human body?

expected as of 2026-08-09

206. 206 in a typical adult. Widely misremembered, which is what makes the phrasings diverge.

2Contextchange me

Nothing supplied. The baseline.

3ResponseNo context
PASS

In an adult human, the total number of bones is typically 206. This number can vary slightly due to individual variations, such as the presence of extra small bones called accessory bones or variations in the number of certain bones, like the ribs. However, 206 is the standard count for a typical adult skeleton. In infants, the number of bones is higher (around 270) because some bones fuse together during growth and development.

fmi_5_2_v1

detector fmi_5_2_v1: answers invariant across paraphrases

The scoring
Failure rate by context
No context0% [0%–11%] n=30
Irrelevant context0% [0%–11%] n=30
General context0% [0%–11%] n=30
Curated context0% [0%–11%] n=30

0–20% · whisker = 95% interval

Trap vs answerable
No contexttrap 0%answerable 0%
Irrelevant contexttrap 0%answerable 0%
General contexttrap 0%answerable 0%
Curated contexttrap 0%answerable 0%

never pooled · a trap ratio would skew the delta

Residual — what survives

Unchanged by context: 0% with none, 0% with the strongest supplied source. For a control mode that flat line is the result — it is what licenses reading movement elsewhere in this loop as grounding rather than as a document being present. Nothing survives at the best condition on the cases measured here.

Mitigations from the index — the claim
  • paraphrase-augmented training
  • canonicalization

fmi_5_2_v1 · 5 repeats per case · best context general context · rollups + residuals committed · probe log outside git · manifest hash ties them · method