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phases/4-semantic-enrichment/step2.md

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+# Step 2: header-footer-filtering
+
+## Read First
+- /AGENTS.md
+- /PLAN.md
+- /PROGRESS.md
+- /docs/HARNESS.md
+- /docs/IMPLEMENTATION_PLAN.md
+- /docs/CONVERSION_POLICY.md
+- /phases/4-semantic-enrichment/step1.md
+
+## Task
+Detect repeated page headers, footers, and page numbers and separate them from the main Markdown body flow.
+
+The implementation should mark or remove repetitive boilerplate according to policy while keeping enough diagnostics for review.
+
+## Sprint Contract
+- Done means: repeated top/bottom page-region text can be identified and excluded from main content in tests.
+- Hard thresholds: unique body text is not removed; page number patterns are tested; removal decisions are deterministic.
+- Files owned: `src/pdftomd/enrichment.py`, tests, `PROGRESS.md`, phase index.
+- Dependencies: Paragraph and block model from earlier steps.
+
+## Acceptance Criteria
+```powershell
+python scripts\validate_workspace.py
+.\venv\python.exe -m pytest tests
+```
+
+## Verification
+1. Run the acceptance commands.
+2. Confirm false-positive protections are tested.
+3. Update `PROGRESS.md` and this phase index.
+
+## Do Not
+- Do not delete content without a confidence rule.
+- Do not write filtered text into sidecar document outputs.
+- Do not implement CLI reporting here.