fix: handle MCP error responses without structuredContent #34
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When an MCP tool returns an error (isError=True), it may only populate the content field with an error message and leave structuredContent as None. The SDK now handles this case gracefully by: 1. Checking isError flag before requiring structuredContent 2. Extracting error message from content field for error responses 3. Returning a proper TaskResult with success=False and the error message 4. Only requiring structuredContent for successful responses (isError=False) This allows the CLI to display agent-provided error messages instead of raising SDK validation errors. Updated tests to cover both cases: - Error responses without structuredContent (now valid) - Success responses without structuredContent (still invalid) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
Split the structuredContent error message across multiple lines to keep each line under 100 characters for linter compliance. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
MagicMock objects return truthy MagicMock instances for any attribute access, so mock_result.isError was returning a truthy value even when not explicitly set. This caused the code to incorrectly treat successful test responses as errors. Now explicitly setting isError=False for all successful response mocks. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Summary
Test plan