When an MCP server returns both content (model-oriented text) and
structuredContent (machine-oriented JSON), the client now combines
them instead of discarding content. The text content becomes the
primary result (what the agent reads), and structuredContent is
included as supplementary metadata.
Previously, structuredContent took full precedence — causing data
loss for servers like Desktop Commander that put the actual file
text in content and metadata in structuredContent.
MCP spec guidance: for conversational/agent UX, prefer content.
- The MCP SDK Pydantic model uses camelCase (structuredContent), not
snake_case (structured_content). The original getattr was a silent no-op.
- When structuredContent is present, return it AS the result instead of
alongside text — the structured payload is the machine-readable data.
- Move test file to tests/tools/ and fix fake class to use camelCase.
- Patch _run_on_mcp_loop in tests so the handler actually executes.
2026-04-07 18:00:01 -07:00
Renamed from tests/test_mcp_structured_content.py (Browse further)
