Updates a specific holdout using JSON Patch operations (RFC 6902). This endpoint allows you to modify individual properties of an existing holdout without replacing the entire resource.

Supported Operations:

• Status transitions: Move holdouts through their lifecycle (draft → running → concluded)
• Configuration updates: Modify traffic allocation, name, description, and other settings
• Archive management: Archive/unarchive concluded holdouts
• Metrics updates: Modify metric configurations (restricted based on status)

State Management & Validation Rules:

• Draft holdouts: All fields can be updated except readonly properties
• Running holdouts: Limited updates allowed; cannot modify metrics or core configuration
• Concluded holdouts: Only name and archived status can be modified
• Status transitions: Must follow proper sequence (draft→running→concluded)
• Traffic allocation: Must be 0-10000 basis points (0-100%)

Automatic Timestamp Management:

• Moving to running status automatically sets start_time to current timestamp
• Moving to concluded status automatically sets end_time to current timestamp

Common Update Patterns:

[
  {"op": "replace", "path": "/name", "value": "Updated Holdout Name"},
  {"op": "replace", "path": "/traffic_allocation", "value": 1500},
  {"op": "replace", "path": "/status", "value": "running"}
]

Important Limitations:

• Cannot modify metrics on running holdouts (prevents mid-experiment changes)
• Cannot archive non-concluded holdouts (must conclude first)
• Cannot update core configuration on running/concluded holdouts
• ReadOnly properties in patch operations are ignored