{
  "schemaVersion": 1,
  "publicSummaryVersion": "2026-09-30",
  "classification": "PUBLIC",
  "title": "Historical branch-isolation and steering test",
  "summary": "On 29 July 2026, laboratory checks created branches from a shared checkpoint, applied distinct steering inputs and verified separate branch histories and filesystems. A test-written marker in one branch did not appear in the others. Identical steering inputs were correctly detected as failing the distinctness requirement. The marker was written by the test harness, not the agent: it proves filesystem isolation, not that an agent obeyed its instructions. Agent behavior remains measured data rather than a guaranteed result.",
  "date": "29 July 2026",
  "scope": "Laboratory or bench evidence; production behavior is not inferred from it.",
  "result": "On 29 July 2026, laboratory checks created branches from a shared checkpoint, applied distinct steering inputs and verified separate branch histories and filesystems. A test-written marker in one branch did not appear in the others. Identical steering inputs were correctly detected as failing the distinctness requirement. The marker was written by the test harness, not the agent: it proves filesystem isolation, not that an agent obeyed its instructions. Agent behavior remains measured data rather than a guaranteed result.",
  "sections": [],
  "currentDeployment": "Not independently verified by this historical evidence.",
  "canonical": "/evidence/phase-5"
}