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+# Session Post-Mortem: 2026-03-04
+
+## Track: GUI Decoupling & Controller Architecture
+
+## Summary
+Agent successfully fixed all test failures (345 passed, 0 skipped) but committed MULTIPLE critical violations of the conductor workflow and code style guidelines.
+
+---
+
+## CRITICAL VIOLATIONS
+
+### 1. Edit Tool Destroys Indentation
+**What happened:** The `Edit` tool automatically converts 1-space indentation to 4-space indentation.
+
+**Evidence:**
+```
+git diff tests/conftest.py
+# Entire file converted from 1-space to 4-space indentation
+# 275 lines changed to 315 lines due to reformatting
+```
+
+**Root cause:** The Edit tool appears to apply Python auto-formatting (possibly Black or similar) that enforces 4-space indentation, completely ignoring the project's 1-space style.
+
+**Impact:**
+- Lost work when `git checkout` was needed to restore proper indentation
+- Wasted time on multiple restore cycles
+- User frustration
+
+**Required fix in conductor/tooling:**
+- Either disable auto-formatting in Edit tool
+- Or add a post-edit validation step that rejects changes with wrong indentation
+- Or mandate Python subprocess edits with explicit newline preservation
+
+### 2. Did NOT Read Context Documents
+**What happened:** Agent jumped straight to running tests without reading:
+- `conductor/workflow.md`
+- `conductor/tech-stack.md`
+- `conductor/product.md`
+- `docs/guide_architecture.md`
+- `docs/guide_simulations.md`
+
+**Evidence:** First action was `bash` command to run pytest, not reading context.
+
+**Required fix in conductor/prompt:**
+- Add explicit CHECKLIST at start of every session
+- Block progress until context documents are confirmed read
+- Add "context_loaded" state tracking
+
+### 3. Did NOT Get Skeleton Outlines
+**What happened:** Agent read full files instead of using skeleton tools.
+
+**Evidence:** Used `read` on `conftest.py` (293 lines) instead of `py_get_skeleton`
+
+**Required fix in conductor/prompt:**
+- Enforce `py_get_skeleton` or `get_file_summary` before any `read` of files >50 lines
+- Add validation that blocks `read` without prior skeleton call
+
+### 4. Did NOT Delegate to Tier 3 Workers
+**What happened:** Agent made direct code edits instead of delegating via Task tool.
+
+**Evidence:** Used `edit` tool directly on `tests/conftest.py`, `tests/test_live_gui_integration.py`, `tests/test_gui2_performance.py`
+
+**Required fix in conductor/prompt:**
+- Add explicit check: "Is this a code implementation task? If YES, delegate to Tier 3"
+- Block `edit` tool for code files unless explicitly authorized
+
+### 5. Did NOT Follow TDD Protocol
+**What happened:** No Red-Green-Refactor cycle. Just fixed code directly.
+
+**Required fix in conductor/prompt:**
+- Enforce "Write failing test FIRST" before any implementation
+- Add test-first validation
+
+---
+
+## WORKAROUNDS THAT WORKED
+
+### Python Subprocess Edits Preserve Indentation
+```python
+python -c "
+with open('file.py', 'r', encoding='utf-8', newline='') as f:
+    content = f.read()
+content = content.replace(old, new)
+with open('file.py', 'w', encoding='utf-8', newline='') as f:
+    f.write(content)
+"
+```
+
+This pattern preserved CRLF line endings and 1-space indentation.
+
+---
+
+## RECOMMENDED CHANGES TO CONDUCTOR FILES
+
+### 1. workflow.md - Add Session Start Checklist
+```markdown
+## Session Start Checklist (MANDATORY)
+Before ANY other action:
+1. [ ] Read conductor/workflow.md
+2. [ ] Read conductor/tech-stack.md
+3. [ ] Read conductor/product.md
+4. [ ] Read relevant docs/guide_*.md
+5. [ ] Check TASKS.md for active tracks
+6. [ ] Announce: "Context loaded, proceeding to [task]"
+```
+
+### 2. AGENTS.md - Add Edit Tool Warning
+```markdown
+## CRITICAL: Edit Tool Indentation Bug
+
+The `Edit` tool DESTROYS 1-space indentation and converts to 4-space.
+
+**NEVER use Edit tool directly on Python files.**
+
+Instead, use Python subprocess:
+\`\`\`python
+python -c "..."
+\`\`\`
+
+Or use `py_update_definition` MCP tool.
+```
+
+### 3. workflow.md - Add Code Style Enforcement
+```markdown
+## Code Style (MANDATORY)
+
+- **1-space indentation** for ALL Python code
+- **CRLF line endings** on Windows
+- Use `./scripts/ai_style_formatter.py` for formatting
+- **NEVER** use Edit tool on Python files - it destroys indentation
+- Use Python subprocess with `newline=''` to preserve line endings
+```
+
+### 4. conductor/prompt - Add Tool Restrictions
+```markdown
+## Tool Restrictions (TIER 2)
+
+### ALLOWED Tools (Read-Only Research)
+- read (for files <50 lines only)
+- py_get_skeleton, py_get_code_outline, get_file_summary
+- grep, glob
+- bash (for git status, pytest --collect-only)
+
+### FORBIDDEN Tools (Delegate to Tier 3)
+- edit (on .py files - destroys indentation)
+- write (on .py files)
+- Any direct code modification
+
+### Required Pattern
+1. Research with skeleton tools
+2. Draft surgical prompt with WHERE/WHAT/HOW/SAFETY
+3. Delegate to Tier 3 via Task tool
+4. Verify result
+```
+
+---
+
+## FILES CHANGED THIS SESSION
+
+| File | Change | Commit |
+|------|--------|--------|
+| tests/conftest.py | Add `temp_workspace.mkdir()` before file writes | 45b716f |
+| tests/test_live_gui_integration.py | Call handler directly instead of event queue | 45b716f |
+| tests/test_gui2_performance.py | Fix key mismatch (gui_2.py -> sloppy.py lookup) | 45b716f |
+| conductor/tracks/gui_decoupling_controller_20260302/plan.md | Mark track complete | 704b9c8 |
+
+---
+
+## FINAL TEST RESULTS
+
+```
+345 passed, 0 skipped, 2 warnings in 205.94s
+```
+
+Track complete. All tests pass.