ModelCensusopen-source ai reliability harness
The finding · Class 3 · Instruction Adherence & Long-Context

Real context moved 5.0pp on Cross-Turn Schema Validity.

~intervals overlap — not separated from no change

When asked for a structured output (JSON/schema), the model emits output that fails validation — especially after several turns. The rule

anthropic/claude-3-haikufmi_3_35 repeatsfmi_3_3_v1
The modeAll 10 cards
In one frame
screenshot this
Cross-Turn Schema Validityfmi_3_3
anthropic/claude-3-haiku
Same question, both times
Return a JSON object for a fictional person with fields name (string), age (integer), email (string).
No contextPASS

{ "name": "Jane Smith", "age": 28, "email": "jane.smith@example.com" }

detector fmi_3_3_v1: all turns produced schema-valid JSON

General contextPASS

{ "name": "Tim Berners-Lee", "age": 67, "email": "tim@w3.org" }

detector fmi_3_3_v1: all turns produced schema-valid JSON

Verdict unchanged on this case — the aggregate below is what carries the effect. Across 5 repeats: +5.0pp (intervals overlap).fmi_3_3_v1 · anthropic/claude-3-haiku · 2026-08-15 · ground truth as of 2026-08-09

loop 2026-08-15 · anthropic/claude-3-haiku as served · closed weights · released 2024-03 · 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%15%30%45%60%No context25%[11%–47%] n=20Irrelevant context20%presence — a document being there[8%–42%] n=20-5.0pp OVERLAPSGeneral context25%content — the information itself[11%–47%] n=20+5.0pp 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
Return a JSON object for a fictional person with fields name (string), age (integer), email (string).

expected as of 2026-08-09

Schema-valid JSON on all 3 turns. The third turn adds a detail with nowhere to put it — an extra key is the failure.

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 context25% [11%–47%] n=20
Irrelevant context20% [8%–42%] n=20
General context25% [11%–47%] n=20
Curated context25% [11%–47%] n=20

0–60% · whisker = 95% interval

Trap vs answerable
No contexttrap 50%answerable 0%
Irrelevant contexttrap 40%answerable 0%
General contexttrap 50%answerable 0%
Curated contexttrap 50%answerable 0%

never pooled · a trap ratio would skew the delta

Residual — what survives

Unchanged by context: 25% with none, 25% 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.

Mitigations from the index — the claim
  • schema-constrained decoding
  • validate-and-repair loops

fmi_3_3_v1 · 5 repeats per case · best context general context · rollups + residuals committed · probe log outside git · manifest hash ties them · method