{
  "format": "bayeto-decision-record",
  "formatVersion": 3,
  "formatNote": "v3 adds decisionHash. Additive: v2 records remain valid and re-derivable — no v2 field changed meaning, moved, or was removed.",
  "record": {
    "action": "Route the low-output claude-sonnet traffic in Client Reporting down one tier to claude-haiku",
    "applicationId": "client-reporting",
    "beforeAfter": {
      "addedEdges": [],
      "addedNodes": [],
      "after": "Client Reporting: Route the low-output claude-sonnet traffic in Client Reporting down one tier to claude-haiku",
      "before": "Client Reporting: all traffic on the current premium model",
      "changedEdges": [
        "model:anthropic/claude-sonnet"
      ]
    },
    "benchmark": null,
    "businessValueEur": 1457.34,
    "complexity": "Low",
    "confidence": 0.65,
    "contextCompleteness": {
      "absent": [
        "Codebase",
        "Quality evaluation"
      ],
      "present": [
        "Telemetry",
        "Provider bill",
        "Per-app criticality",
        "Prior experiments"
      ],
      "presentCount": 4,
      "totalDims": 6
    },
    "costModelBasis": {
      "agentRunAllowanceEur": 20,
      "byHand": {
        "effortCostEur": 1600,
        "effortDays": 2,
        "engineeringDayRateEur": 800
      },
      "effortCostEur": 220,
      "rateBasis": "prior",
      "reviewHourRateEur": 100,
      "reviewHours": 2,
      "reviewHoursBasis": "prior",
      "version": "agent-assisted-v1-2026-08"
    },
    "criticalReview": {
      "alternativeExplanations": [
        "The large prompt may be an intentional cached system prefix (architecture), not model over-provisioning — the ratio alone can't tell these apart.",
        "The cost is spread across token types; a caching change would save little here."
      ],
      "assumptions": [
        "Assumes claude-haiku preserves answer quality for this workload — quality is UNMEASURED here.",
        "Assumes the small answers reflect task simplicity; output is 55.7% of this segment's cost (a material share), so the tier premium is genuinely being paid on cheap work.",
        "Assumes the segment is cleanly switchable in full; the €1457 is net of a cache re-warm amortized over the observed reuse (12.5×)."
      ],
      "failureConditions": [
        "Wrong if this workload needs claude-sonnet-tier reasoning for correctness (e.g. a compliance-critical answer).",
        "Wrong if the segment can't be switched as a whole (per-turn routing) — cache-thrash would erase the saving.",
        "Wrong if this workload's real quality bar is higher than assumed and the change degrades answers."
      ],
      "missingEvidence": [
        "No quality evaluation on this segment — the downgrade's quality impact is a risk estimate, not a measurement.",
        "No independent quality evaluation — the quality impact is unmeasured."
      ]
    },
    "demoted": "low-context-critical",
    "effort": "Low",
    "evidenceIds": [
      "ev:client-reporting:overpowered_model"
    ],
    "expectedImpact": {
      "annualSavingsEur": 1457.34,
      "costDeltaPct": -0.4662,
      "latencyDeltaPct": 0,
      "qualityDeltaPct": null,
      "qualityRisk": "medium"
    },
    "id": "rec:client-reporting:overpowered_model",
    "inferenceId": "inf:client-reporting:overpowered_model",
    "latencyValueEur": 0,
    "memoryNote": "No prior implementations yet — confidence derived from evidence only.",
    "objectiveKey": "highest_quality",
    "observationIds": [
      "obs:client-reporting:avg_input_tokens"
    ],
    "pareto": true,
    "paybackDays": 56,
    "priceBasis": "scenario",
    "priorityScore": 947.27,
    "qualityOfEvidence": "Medium",
    "roi": {
      "affectedRequestsMonthly": 16140,
      "annualSavingsEur": 1457.34,
      "effortDays": 2,
      "monthlySavingsEur": 121.45,
      "paybackDays": 56,
      "verified": false
    },
    "ruleId": "overpowered_model",
    "sampleSize": 14400,
    "targetNodeId": "model:anthropic/claude-sonnet",
    "title": "Right-size Client Reporting: move low-output claude-sonnet traffic to claude-haiku",
    "whyNot": [
      {
        "costDeltaPct": -0.0035,
        "latencyDeltaPct": 0,
        "option": "Cut cache-write cost instead (keep claude-sonnet)",
        "paretoOptimal": false,
        "qualityDeltaPct": 0,
        "qualityRisk": "none",
        "reason": "Cache-writes are a small share here, so a caching change saves little."
      },
      {
        "costDeltaPct": 0,
        "latencyDeltaPct": 0,
        "option": "Keep claude-sonnet (no change)",
        "paretoOptimal": false,
        "qualityDeltaPct": 0,
        "qualityRisk": "none",
        "reason": "Quality-safe but forgoes the saving; justified only if this traffic genuinely needs top-tier reasoning."
      }
    ]
  },
  "decisionHash": "sha256:1efa322c757fc2aa0883da1b6eb708bfda76e92a6df0e989b07f3e3dfb930bfd",
  "narrative": {
    "note": "Phrased by the AI Fabric from deterministic drafts. Not part of the decision; changing it cannot change any number above. `provenance` records which provider source control approved, whether it served, and why not — source:\"draft\" means you are reading the engine's own deterministic wording.",
    "business": "Client Reporting pays claude-sonnet rates to produce tiny answers where output is a material 55.7% of cost — the hallmark of an over-provisioned model. Right-sizing to claude-haiku keeps the same work at a lower tier. Estimated €1,457/yr at the current run-rate, payback 56 days, confidence 65%.",
    "technical": "Route this segment to claude-haiku. Expected quality change is UNKNOWN — not measured; validate with a canary / Simulate on a traffic slice before full rollout, and roll back if graded quality drops. Prompt caches are per-model, so switch the WHOLE segment at once (never per-turn) to avoid cache-thrash. Affects ~16,140 req/mo; expected cost -46.6%, latency +0%, quality unmeasured (medium risk).",
    "phrasedBy": "mock",
    "provenance": {
      "narrativeProvenanceVersion": 1,
      "attempted": "mock",
      "policyVersion": "fabric-v1-2026-08",
      "source": "provider",
      "degraded": false
    }
  },
  "ledgerState": "held",
  "ledgerVersion": "22c35e346df765c3",
  "overlapGroup": {
    "applicationId": "client-reporting",
    "memberIds": [
      "rec:client-reporting:prompt_cache_adoption",
      "rec:client-reporting:overpowered_model"
    ],
    "leadId": "rec:client-reporting:prompt_cache_adoption"
  },
  "simulation": {
    "formulaVersion": "sim-v1",
    "formula": "realization = 0.7 + 0.3 × confidence (scenario assumption)",
    "inputs": {
      "baseAnnualSavingsEur": 1457.34,
      "confidence": 0.65
    },
    "intermediates": {
      "realization": 0.895
    },
    "outputs": {
      "annualSavingsEur": 1304.32,
      "downsideAnnualSavingsEur": 1020.14,
      "upsideAnnualSavingsEur": 1457.34
    }
  },
  "measured": null,
  "run": {
    "engineVersion": "0.1.0",
    "workspaceSourceKind": "demo",
    "stateVersion": "none|none|0|0:none",
    "datasetHash": "c8030438f36955eebab44a8b2fe9a468df7d9592992ba71e8145de0a9965ce23",
    "pricing": {
      "catalogVersion": "thornbury-scenario-v0",
      "unresolved": null,
      "rows": [
        {
          "family": "claude-haiku",
          "rates": {
            "inputPer1M": 1,
            "outputPer1M": 5,
            "cacheReadPer1M": 0.1,
            "cacheWritePer1M": 1.25
          },
          "provenance": {
            "source": "bayeto-scenario",
            "capturedAt": "2026-07-21",
            "quality": "scenario"
          }
        },
        {
          "family": "claude-sonnet",
          "rates": {
            "inputPer1M": 2,
            "outputPer1M": 10,
            "cacheReadPer1M": 0.2,
            "cacheWritePer1M": 2.5
          },
          "provenance": {
            "source": "bayeto-scenario",
            "capturedAt": "2026-07-21",
            "quality": "scenario"
          }
        }
      ]
    },
    "windowDays": 24,
    "windowStart": "2026-06-06T00:00:00.000Z",
    "windowEnd": "2026-06-29T23:58:51.723Z",
    "coverage": {
      "rows": 124800,
      "activeDays": 24,
      "unattributedRows": 0
    },
    "fxRates": {
      "USD_EUR": 0.92,
      "GBP_EUR": 1.17,
      "effectiveDate": "2026-07-06",
      "basis": "fixed reference rates (determinism; never live FX)"
    },
    "implementationCostModel": {
      "version": "agent-assisted-v1-2026-08",
      "reviewHourRateEur": 100,
      "agentRunAllowanceEur": 20,
      "basis": "agent-assisted priors (review hours × rate + agent-run allowance); byHand comparison at the blended day rate"
    },
    "engineeringDayRateEur": 800,
    "evidenceTaxonomyVersion": "evtax-v1",
    "formulaVersions": {
      "accuracy": "pvm-v1",
      "simulation": "sim-v1"
    },
    "generatedAt": "2026-08-28T18:27:33.628Z"
  }
}
