{
  "sha": "74541bab17270c35f4418d4e543d85628632ed8f",
  "platform": "Linux x64; Claude Code 2.1.303; Chromium via T3 browser; isolated dev state",
  "commands": [
    "git fetch origin main",
    "git worktree add ~/wt/issue-16672 origin/main",
    "vp install",
    "vp run dev"
  ],
  "steps": [
    "Provider settings > Claude > Add custom model claude-sonnet-4-5-20250929 > Edit > Reasoning + Thinking > Save",
    "Composer select custom model; explicitly High and Thinking Off; send prompt",
    "Restart own dev server; send fresh-process prompt with same saved options",
    "Select built-in Claude Haiku 4.5, Thinking Off; send control prompt"
  ],
  "runs": [
    {
      "ordinal": 1,
      "modelSelection": {
        "instanceId": "claudeAgent",
        "model": "claude-sonnet-4-5-20250929"
      },
      "status": "completed",
      "requestedAt": "2026-10-21T09:35:50.684Z",
      "completedAt": "2026-10-21T09:36:01.716Z"
    },
    {
      "ordinal": 2,
      "modelSelection": {
        "instanceId": "claudeAgent",
        "model": "claude-sonnet-4-5-20250929",
        "options": [
          {
            "id": "effort",
            "value": "high"
          },
          {
            "id": "thinking",
            "value": false
          }
        ]
      },
      "status": "completed",
      "requestedAt": "2026-10-21T09:37:47.873Z",
      "completedAt": "2026-10-21T09:37:52.685Z"
    },
    {
      "ordinal": 3,
      "modelSelection": {
        "instanceId": "claudeAgent",
        "model": "claude-sonnet-4-5-20250929",
        "options": [
          {
            "id": "effort",
            "value": "high"
          },
          {
            "id": "thinking",
            "value": false
          }
        ]
      },
      "status": "completed",
      "requestedAt": "2026-10-21T09:38:57.086Z",
      "completedAt": "2026-10-21T09:39:00.988Z"
    },
    {
      "ordinal": 4,
      "modelSelection": {
        "instanceId": "claudeAgent",
        "model": "claude-haiku-4-5",
        "options": [
          {
            "id": "thinking",
            "value": false
          }
        ]
      },
      "status": "failed",
      "requestedAt": "2026-10-21T09:39:58.011Z",
      "completedAt": "2026-10-21T09:39:59.358Z"
    },
    {
      "ordinal": 5,
      "modelSelection": {
        "instanceId": "claudeAgent",
        "model": "claude-sonnet-4-5-20250929",
        "options": [
          {
            "id": "effort",
            "value": "high"
          },
          {
            "id": "thinking",
            "value": true
          }
        ]
      },
      "status": "completed",
      "requestedAt": "2026-10-21T09:40:20.603Z",
      "completedAt": "2026-10-21T09:40:26.544Z"
    }
  ],
  "queryOpens": [
    {
      "timestamp": "2026-10-21T09:35:52.308Z",
      "options": {
        "model": "claude-sonnet-4-5-20250929",
        "settings": {
          "showThinkingSummaries": true
        }
      }
    },
    {
      "timestamp": "2026-10-21T09:38:58.323Z",
      "options": {
        "model": "claude-sonnet-4-5-20250929",
        "settings": {
          "showThinkingSummaries": true
        },
        "effort": "high"
      }
    },
    {
      "timestamp": "2026-10-21T09:39:59.056Z",
      "options": {
        "model": "claude-haiku-4-5",
        "settings": {
          "alwaysThinkingEnabled": false
        }
      }
    },
    {
      "timestamp": "2026-10-21T09:40:22.338Z",
      "options": {
        "model": "claude-sonnet-4-5-20250929",
        "settings": {
          "showThinkingSummaries": true
        },
        "effort": "high"
      }
    }
  ],
  "result": "At the tested SHA, explicit high effort reaches query.open; the partialFixCommit introduced that fallback. Custom Thinking false remains absent from query.open. Built-in Thinking false is applied; its upstream turn returns 400 unknown provider.",
  "customModels": [
    {
      "slug": "claude-sonnet-4-5-20250929",
      "capabilities": {
        "optionDescriptors": [
          {
            "id": "effort",
            "label": "Reasoning",
            "type": "select",
            "options": [
              {
                "id": "low",
                "label": "Low"
              },
              {
                "id": "medium",
                "label": "Medium"
              },
              {
                "id": "high",
                "label": "High",
                "isDefault": true
              },
              {
                "id": "xhigh",
                "label": "Extra High"
              },
              {
                "id": "max",
                "label": "Max"
              }
            ],
            "currentValue": "high"
          },
          {
            "id": "thinking",
            "label": "Thinking",
            "type": "boolean"
          }
        ]
      }
    }
  ],
  "partialFixCommit": "76f57f9b84ee53d9b998710417d9f8bf02d192dc"
}