- McpTool.execute() now forces the real session_id from current_session_id
  ContextVar, preventing LLM hallucinations of wrong UUIDs (ghost-session bug).
- For navi-3d MCP server, source_path/output_path are normalized to basename
  to prevent double path nesting when the LLM passes full relative paths.
- Updated MCP tool descriptions to ask for filenames only.
- Added system prompt instructions in context_builder and subagent_runner
  reminding the model to pass bare filenames to navi-3d tools.

396 passed, 1 skipped

All three tool handlers (compile_scad, render_stl, lint_scad) were
calling async core functions without await from synchronous def bodies.
This caused FastMCP to receive a coroutine object instead of a dict,
which then failed JSON serialization with:
  Object of type coroutine is not JSON serializable

Fix: convert tool handlers to async def and await the underlying
compile_scad / render_stl / lint_scad calls before passing to _json().

Tested via stdio_client — lint_scad now returns clean JSON result.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

The MCP server registered tools with `_tool` suffix (e.g. lint_scad_tool)
but mcp_servers.json groups listed bare names (lint_scad). This caused
_tool_list() to look for mcp_navi-3d_lint_scad which never existed in the
registry — the actual registered tool was mcp_navi-3d_lint_scad_tool.

Fix: explicitly set name= on @mcp.tool() decorators so MCP tool names
match the group whitelist in mcp_servers.json.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Phase 0 — Fix MCP error propagation:
- McpClient.call_tool now returns (output, is_error) tuple
- McpTool.execute sets success=False when MCP reports isError=True
- Fixes silent failures where MCP errors looked like success

Phase 1 — Create mcp-server-navi-3d:
- New standalone MCP server in mcp-servers/navi-3d/
- Tools: compile_scad, render_stl, lint_scad
- Session-scoped path resolution via SESSION_FILES_DIR env
- Anti-escape validation for security
- Includes tests/unit/test_scad_analyze.py

Phase 2 — Remove from Navi core:
- Deleted navi/tools/{model_3d,render_3d,scad_lint}.py
- Removed from registry.py builtins and navi/tools/__init__.py
- Updated pyproject.toml testpaths to exclude mcp-servers/

Phase 3 — Wire into Navi config:
- Added navi-3d block to mcp_servers.json (SSE on :8002)
- Updated modeler_3d profile: mcp_servers + updated system_prompt
- All old tool names replaced with mcp_navi-3d_* equivalents

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>