fix(mcp): BUG-003 — replace invalid "type":"json" content blocks with "type":"text"#16
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… "type":"text"
MCP 2025-11-25 spec only allows text/image/audio/resource_link/resource
as content types. All 27 tool handlers were returning "type":"json" which
causes Zod union validation failures in spec-compliant clients (complete
protocol failure from any real MCP bridge).
Changes:
- Add text_content() private helper: serializes Value payload to a JSON
string and wraps it in a {"type":"text","text":...} content block
- Replace all 27 "type":"json" content blocks via text_content()
- Add handle_pipeline_status() handler in mcp_adapter — eliminates the
last hand-rolled response envelope in ledgerr-mcp-server.rs
- Update all test files: replace ["json"] content access with
parse_response_payload() helper that deserializes the text field
- Mark BUG-003 resolved in docs/bugs/SUMMARY.md
- Add v1.3.8 entry to CHANGELOG.md
All 86 tests pass.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
"type": "json"content blocks.jsonis not a valid MCP 2025-11-25 content type — spec only allowstext,image,audio,resource_link,resource. This caused Zod union validation failures in any spec-compliant MCP client (complete protocol failure via Cowork/Claude bridge).text_content(payload: Value) -> Valueprivate helper that serializes the JSON payload to a string and wraps it in{"type":"text","text":"..."}.handle_pipeline_status()tomcp_adapter— eliminated the last hand-rolled response envelope inledgerr-mcp-server.rs.content[0]["json"]access with aparse_response_payload()helper that deserializes from thetextfield.Test plan
cargo test -p ledgerr-mcp— 86 tests, 0 failures"type": "json"occurrences remain inmcp_adapter.rsdocs/bugs/SUMMARY.md🤖 Generated with Claude Code