{
  "schema": "vedokrok.public-item.v1",
  "release_id": "MHC-RPUB-20260920-75ad787a",
  "url": "/knowledge/keep-a-hypothesis-test-result-ledger",
  "id": "MHC-D-RESEARCH-0299",
  "version": "0.1.0",
  "title": "Keep a hypothesis–test–result ledger",
  "summary": "Without notes, troubleshooting quietly turns into reruns and folklore.",
  "kind": "template",
  "body": "Record each active hypothesis, the test used, the observed result and what changed because of it. Also record deliberate system changes and how to undo them. Keep entries factual enough that a new investigator can see which paths are closed, which remain open and whether the environment has drifted during the search.",
  "limits": [
    "The ledger is not a dumping ground for secrets, personal data or unverified blame."
  ],
  "topics": [
    "union-diagnostic-incident-work"
  ],
  "intents": [],
  "source_ids": [
    "RS-A4A16C807A94C9D8"
  ],
  "evidence": [
    {
      "claim": "Google SRE recommends recording hypotheses, tests and observed results so investigations do not repeat work or lose the path back to the pre-test state.",
      "source_id": "RS-A4A16C807A94C9D8",
      "role": "supports",
      "note": "Do not place credentials, regulated data or unnecessary personal information in an incident notebook.",
      "locator": "Test and Treat; investigation notes"
    }
  ],
  "use_when": [
    "A diagnosis spans many attempts, people or configuration changes."
  ],
  "avoid_when": [
    "The ledger is not a dumping ground for secrets, personal data or unverified blame."
  ],
  "example": "After increasing a timeout for one test, record both the latency result and the fact that the timeout must be restored.",
  "check": "A second person can avoid repeating a completed test and can reconstruct material state changes.",
  "template": "[time] Hypothesis: [hypothesis]. Test/change: [action]. Observed: [result]. Interpretation: [what this weakens or supports]. Rollback/state note: [state].",
  "sources": [
    {
      "id": "RS-A4A16C807A94C9D8",
      "title": "Effective Troubleshooting",
      "url": "https://sre.google/sre-book/effective-troubleshooting/"
    }
  ],
  "relations": [
    {
      "from": "MHC-D-RESEARCH-0299",
      "to": "MHC-D-RESEARCH-0306",
      "type": "useful_with",
      "url": "/knowledge/give-every-postmortem-action-a-verifiable-finish"
    }
  ],
  "collections": [
    {
      "id": "RC-6F9B0E6D320D1467",
      "title": "Find the fault without making the incident harder to understand",
      "url": "/collections/find-the-fault-without-making-the-incident-harder-to-understand"
    }
  ]
}