add files

phases/3-formula-pipeline/step2.md

@@ -0,0 +1,38 @@
+# Step 2: latex-validation-repair
+
+## Read First
+- /AGENTS.md
+- /PLAN.md
+- /PROGRESS.md
+- /docs/HARNESS.md
+- /docs/IMPLEMENTATION_PLAN.md
+- /docs/CONVERSION_POLICY.md
+- /phases/0-harness-foundation/step3.md
+- /phases/3-formula-pipeline/step1.md
+
+## Task
+Implement LaTeX and Markdown math validation for formula outputs, plus explicit repair helpers for safe cases.
+
+Validation should cover delimiter balance and common `\begin{...}` / `\end{...}` pairs.
+
+## Sprint Contract
+- Done means: formula output validation returns actionable diagnostics and tested repairs for narrow, deterministic cases.
+- Hard thresholds: validation does not silently mutate math; unrepairable failures fall back to Marker text; delimiter tests include both inline and block math.
+- Files owned: `src/pdftomd/formulas.py`, `src/pdftomd/quality.py`, tests, `PROGRESS.md`, phase index.
+- Dependencies: Phase 0 quality gates and Step 1 Nougat adapter.
+
+## Acceptance Criteria
+```powershell
+python scripts\validate_workspace.py
+.\venv\python.exe -m pytest tests
+```
+
+## Verification
+1. Run the acceptance commands.
+2. Confirm broken delimiter and environment examples are covered.
+3. Update `PROGRESS.md` and this phase index.
+
+## Do Not
+- Do not build a broad LaTeX parser from scratch.
+- Do not use LLM repair.
+- Do not hide validation failures.