codebase-memory-mcp shipped a wire-size optimization that returned `{}` to every schema-honoring client, then patched it 17 hours later.

DeusData's repo (38,513 stars) stopped duplicating tool payloads into structuredContent while every tool still declared a permissive outputSchema, so under the MCP spec search_graph, trace_path, query_graph, and three more all returned empty objects to Claude Code and Codex. The verification sweep found two more bugs with the identical shape (empty result, success status). The maintainers publicly conceded their own tests "pinned the broken behavior as correct" at unit, binary-smoke, and CI level. Green pipeline, agreeing with the bug. That's the failure mode I'd bet most of us have shipped this year.