fix: distinguish task completion from operation success

[bokelley]

Problem

When agents return status: completed with success: false in the response data, the library incorrectly reported the operation as successful. This caused silent failures:

Example: Wonderstruck Media Buy

Agent response:

{
  "success": false,
  "message": "Missing required parameters: ['product_ids', 'total_budget', 'flight_start_date', 'flight_end_date']"
}

Library returned:

{ success: true, status: 'completed', data: { success: false, ... } }

Result: Script printed "✅ SUCCESS! Media buy created" even though the operation failed and no media buy was created.

Root Cause

The library conflated two different concepts:

1. Task completion - Did the API call complete? (protocol level)
2. Operation success - Did the business operation succeed? (application level)

When A2A/MCP returns status: completed, it means "I successfully processed your request and returned a response." It does NOT mean "the operation succeeded."

Solution

Check response.data.success to determine actual operation success:

• If data.success === false, set result.success = false and include error field
• If data.success is undefined/missing, assume success (backward compatible)
• Extract error message from data.message into result.error

Changes

Applied to all completion code paths in TaskExecutor.ts:

1. Immediate completion (ADCP_STATUS.COMPLETED)
2. Polling completion (waitForWorkingCompletion)
3. Task polling (pollTaskCompletion)
4. Default/unknown status handling

// Before
return { success: true, status: 'completed', data: completedData };

// After
const operationSuccess = completedData?.success !== false;
return {
  success: operationSuccess,
  status: 'completed',
  data: completedData,
  error: operationSuccess ? undefined : (completedData?.message || 'Operation failed')
};

Impact

Before:

✅ SUCCESS! Media buy created
🎉 Media buy successfully created on Wonderstruck!
   Your 300x250 creative is now running.

After:

❌ FAILED to create media buy

Error Details:
   Error: Missing required parameters: ['product_ids', 'total_budget', 'flight_start_date', 'flight_end_date']
   Status: completed
   Response Time: 75ms

Backward Compatibility

✅ Fully backward compatible - Agents that don't return a success field are unaffected. Only agents that explicitly return success: false will trigger the new failure handling.

Testing

• Build passes
• Tested with Wonderstruck agent - correctly reports failure
• Error message properly surfaced to scripts
• No changes to existing test expectations needed

🤖 Generated with Claude Code

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