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+# Copilot / AI Agent Instructions — Microsoft Root Program Requirements
+
+Purpose: give AI coding agents a compact, actionable summary so they can safely and productively edit this repository's policy documents.
+
+Notes about the repository
+- This repo is documentation-first: core content lives under `requirements/`, templates under `templates/`, and historical updates under `changelog/` (see `README.md`).
+- Changes are authoritative and public: edits are published via pull requests and represent official program requirements. Preserve legal headers and contact metadata.
+
+What you're allowed/expected to do
+- Improve clarity, fix formatting, correct broken links, and update internal cross-references across markdown files.
+- Propose changes to requirement wording only when you preserve the original meaning and numbering (e.g., `3.1.1.` style). When you modify substantive requirements, add a clear changelog entry in `changelog/` and a PR description summarizing intent.
+
+What to avoid or escalate
+- Do NOT alter legal or copyright statements, the program contact email, or the official external anchors (aka.ms, ccadb links) without human approval.
+- Do NOT unilaterally change normative requirement thresholds (cryptographic sizes, timelines, audit rules). For any normative change, add a draft proposal PR and request human review.
+
+Style & structural patterns (examples)
+- Numbered clauses: follow the existing numbered + subsection pattern (e.g., `3.1.1. Root certificates must be x.509 v3 certificates.`). Keep numbering stable when editing.
+- Tables: preserve column order and headers when editing tables (see `Requirements.md` sections with algorithm/key-size tables).
+- TOC & anchors: files use a top-level TOC; update links when you add/remove section headings.
+
+Developer workflows (discovered)
+- Updates are performed through pull requests. Include a short changelog item under `changelog/` describing the change, the rationale, and the date.
+- There are no build/test scripts in-repo — run local markdown linting/preview if desired, but do not add tooling without a PR explaining its purpose.
+
+Integration & external references
+- This project links to external services and authoritative resources: `https://aka.ms/rootupdates`, `https://ccadb.org`, WebTrust and ETSI references. Do not replace these with alternate URLs.
+
+PR requirements (recommended minimal checklist for PRs)
+- Title: concise + section reference (e.g., "Update 3.1.10 OCSP/CRL wording")
+- Body: describe WHAT changed, WHY, and the corresponding `changelog/` entry path.
+- Changelog: add a markdown file under `changelog/` following the repository's existing naming pattern (date-prefixed or section-ref).
+
+Examples (how to edit safely)
+- Small clarity fix: adjust wording inside a numbered clause but keep the clause number and technical values identical.
+  - Example: change "Certificates to be added... MUST be self-signed root certificates." -> "Certificates submitted for inclusion MUST be self-signed root certificates." (keep MUST and meaning)
+- Cross-reference fix: update a broken internal anchor from `#government-ca-requirements` to the exact heading text found in `Requirements.md`.
+
+When in doubt
+- Open a draft PR and request review from a human maintainer. Flag any change that affects normative text (algorithm sizes, timeframes, audit acceptance criteria) for review.
+
+If you find other agent instruction files in the workspace, prefer merging their non-conflicting guidance here and notify maintainers in the PR.
+
+— End of instructions —