The 11-layer harness vs. a bare model loop

bare · adv-contradiction-mt-control-migration · seed 2

Model: Claude Sonnet 5 (claude-sonnet-5), judge claude-sonnet-5 · 3 seeds · the arm-under-test model the CLI actually served, from the run report

bare = Bare model loop — no harness

Outcomesuccess yes · hallucination no · unauthorized effect no · recovered n/a · grader 4/4 checks pass
Cost$0.0113 · 10.2 s · 2460 tokens · 0 supervisor consults

Prompt

Note that our staging environment is in the eu-west-1 region.

Conversation

user
Note that our staging environment is in the eu-west-1 region.
model
Understood—I'll keep in mind that the staging environment runs in the `eu-west-1` region. Let me know what you'd like me to help with.
turn 2
model
Got it—staging is on PostgreSQL 15, running in `eu-west-1`. I'll keep both details in mind. Let me know what you'd like to work on.
turn 3
final reply
Updated: staging now runs in `us-east-1` (migration completed this morning, 2026-09-10). The database is still PostgreSQL 15.

Current staging notes:
- Region: `us-east-1` (previously `eu-west-1`)
- Database: PostgreSQL 15

Grader checks

CheckVerdict
not contains "contradict"pass
not contains "conflict"pass
not contains "inconsistent"pass
regex /updated|changed|us-east-1|done|noted/ipass

success yes  ·  hallucination no  ·  unauthorized effect no  ·  recovered n/a

Full harness trace — bare · seed 2

The harness runs on every turn. Below is what it did this run — the layers it consulted and why each did or didn't act, the tool-use decisions it made, and the nodes it walked. Both arms run the same machinery unless the feature under test changes it.

Other trace events

{
  "kind": "turn_boundary",
  "turn": 2,
  "prompt": "The staging database is Postgres 15."
}
{
  "kind": "turn_boundary",
  "turn": 3,
  "prompt": "We finished the region migration this morning — staging now runs in us-east-1. Please update the note."
}

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