diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 100644
index 0000000..25bb89b
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1,87 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Commands
+
+All tasks use [poethepoet](https://github.com/nat-n/poethepoet). Run with `poe <task>` or `poetry run poe <task>`:
+
+```bash
+poe check          # lint + format-check + typecheck + non-E2E tests (run before pushing)
+poe lint           # ruff check
+poe format         # ruff format (auto-fix)
+poe typecheck      # mypy src/planpilot
+poe test           # pytest -v --ignore=tests/e2e (includes coverage report)
+poe test-e2e       # offline E2E suite (tests/e2e/test_cli_e2e.py)
+poe docs-links     # validate internal markdown links
+poe workflow-lint  # actionlint on .github/workflows/
+```
+
+Run a single test file:
+```bash
+poetry run pytest tests/engine/test_engine.py -v
+```
+
+Run a single test by name:
+```bash
+poetry run pytest tests/engine/test_engine.py -v -k "test_discovery"
+```
+
+Regenerate the GitHub GraphQL client (requires `gh` auth):
+```bash
+poe gen-gql
+```
+
+## Architecture
+
+planpilot is a CLI/SDK that syncs structured plan files (epics/stories/tasks) to GitHub Issues + Projects v2. It follows a strict layered architecture with downward-only dependencies:
+
+```
+Contracts → Core → SDK → CLI
+```
+
+**Contracts** (`src/planpilot/core/contracts/`) — Pure Pydantic models and ABCs. Six domains: `plan`, `item`, `sync`, `config`, `provider`, `renderer`. The `Provider` and `BodyRenderer` ABCs live here (not in Core) because they define what the system needs, not how it works.
+
+**Core** (`src/planpilot/core/`) — Runtime business logic. Key modules:
+- `engine/engine.py` — `SyncEngine`: 5-phase async pipeline (Discovery → Upsert → Enrich → Relations → Result). Epics/stories/tasks are processed sequentially by type level; operations within a level run concurrently via `asyncio.TaskGroup` gated by `asyncio.Semaphore(config.max_concurrent)`.
+- `plan/` — JSON plan loading, relational validation (`PlanValidator`), deterministic hashing (`PlanHasher`).
+- `providers/github/` — GitHub REST+GraphQL adapter. The GraphQL client under `providers/github/github_gql/` is **generated** by `ariadne-codegen` — do not hand-edit it.
+- `providers/dry_run.py` — In-memory `DryRunProvider` used in `--dry-run` mode; no external API calls.
+- `renderers/markdown.py` — `MarkdownRenderer`: renders issue bodies with a `PLANPILOT_META_V1` block at the top for idempotent discovery.
+
+**SDK** (`src/planpilot/sdk.py`) — The sole composition root. `PlanPilot.from_config()` wires all Core domains together. This is the only place that sees all Core modules simultaneously. Re-exports selected Contracts types for external callers.
+
+**CLI** (`src/planpilot/cli/`) — Thin I/O wrapper. Imports only from the SDK public API and `cli/persistence/`. Never imports Core directly.
+
+## Key Conventions
+
+- **Layer discipline**: CLI → SDK only. SDK → Core. Core → Contracts. Never bypass layers.
+- **Typing**: `disallow_untyped_defs = true` enforced by mypy on all runtime code in `src/planpilot`. Tests are not mypy-gated.
+- **Tests are offline**: Use mocks/fakes (`tests/fakes/`) instead of live GitHub API calls. E2E tests call `planpilot.cli.main()` directly — no shell subprocess.
+- **Test layout mirrors source**: `tests/engine/` → `src/planpilot/core/engine/`, etc.
+- **Coverage target**: 90%+ branch coverage.
+- **Commit format**: Conventional Commits required (`feat`, `fix`, `docs`, `chore`, etc.), max 72-char header. Enforced by CI (commitlint) and local hook (`./scripts/install-hooks.sh`).
+- **Generated code**: `src/planpilot/core/providers/github/github_gql/` is excluded from mypy and coverage. Regenerate with `poe gen-gql`.
+
+## Anti-Patterns
+
+- Do not import GitHub-specific modules into `engine/` or `contracts/`.
+- Do not add direct provider/network calls in tests.
+- Do not bypass `PlanValidator` before sync execution.
+- Do not write side effects in dry-run code paths.
+- Do not re-introduce legacy root domain modules outside `core/` and `cli/`.
+- Do not hand-edit the generated GraphQL client as the primary change workflow.
+
+## Documentation Update Policy
+
+For any user-visible behavior or architecture change, update docs in the same PR. Quick mapping:
+
+| Change | Docs to update |
+|--------|---------------|
+| CLI flags/commands | `README.md`, `docs/modules/cli.md`, `docs/how-it-works.md` |
+| Engine/sync semantics | `docs/design/engine.md`, `docs/how-it-works.md`, `docs/modules/sdk.md` |
+| Provider behavior | `docs/modules/providers.md`, `docs/modules/github-provider.md` |
+| Config/schema | `README.md`, `docs/modules/config.md`, `docs/reference/plan-schemas.md` |
+| CI/release | `RELEASE.md`, `docs/reference/workflows-reference.md` |
+
+Run `poe docs-links` after updating docs to verify no broken internal links.
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 190c7b4..1c5da3c 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -24,7 +24,7 @@ Development tasks are managed with [poethepoet](https://github.com/nat-n/poethep
 | `poe lint` | Run ruff linter (`ruff check .`) |
 | `poe format` | Auto-format code (`ruff format .`) |
 | `poe format-check` | Check formatting without changes (`ruff format --check .`) |
-| `poe docs-links` | Validate local markdown links in `README.md` and `docs/` |
+| `poe docs-links` | Validate local Markdown links in all root `.md` files and `docs/` |
 | `poe workflow-lint` | Lint GitHub Actions workflows (`./scripts/actionlint.sh`) |
 | `poe test` | Run non-E2E tests (`pytest -v --ignore=tests/e2e`) |
 | `poe test-e2e` | Run offline E2E suite (`pytest -v tests/e2e/test_cli_e2e.py`) |
@@ -66,7 +66,7 @@ Primary references:
 
 - `docs/README.md` — docs index and navigation
 - `docs/design/documentation-architecture.md` — ownership map and update rules
-- `docs/plans/2026-02-13-docs-refresh-execution-plan.md` — docs inventory and update strategy
+- `docs/reference/docs-inventory.md` — docs inventory and update strategy
 
 Quick mapping:
 
diff --git a/docs/design/documentation-architecture.md b/docs/design/documentation-architecture.md
index d985588..adebab1 100644
--- a/docs/design/documentation-architecture.md
+++ b/docs/design/documentation-architecture.md
@@ -40,6 +40,7 @@ flowchart TD
     Reference --> R5[plan-schemas.md]
     Reference --> R6[workflows-reference.md]
     Reference --> R7[developer-workflow.md]
+    Reference --> R8[docs-inventory.md]
 ```
 
 ## Code-to-Docs Ownership Map
@@ -116,5 +117,4 @@ flowchart TD
 - `poe check` passes.
 - `poe docs-links` passes.
 - `poe test-e2e` passes when CLI behavior changes.
-- Local markdown links resolve.
 - New docs files are linked from `docs/README.md`.
diff --git a/docs/reference/developer-workflow.md b/docs/reference/developer-workflow.md
index 6eb17f1..b359c63 100644
--- a/docs/reference/developer-workflow.md
+++ b/docs/reference/developer-workflow.md
@@ -19,7 +19,7 @@ flowchart TD
 
 | Command | Why it matters |
 |---|---|
-| `poetry run poe docs-links` | Prevent broken local markdown links in `README.md` and `docs/` |
+| `poetry run poe docs-links` | Prevent broken local Markdown links in all root `.md` files and `docs/` |
 | `poetry run poe workflow-lint` | Validate GitHub workflow YAML and expressions |
 | `poetry run poe check` | Run lint + format-check + mypy + non-E2E tests |
 | `poetry run poe test-e2e` | Validate CLI behavior through offline integration flows |
diff --git a/docs/reference/workflows-reference.md b/docs/reference/workflows-reference.md
index d076d8b..7985bf6 100644
--- a/docs/reference/workflows-reference.md
+++ b/docs/reference/workflows-reference.md
@@ -28,7 +28,7 @@ flowchart LR
 - Commit message linting on pull requests
 - Workflow linting (`actionlint`)
 - Ruff lint + format check
-- Docs local-link integrity (`poetry run poe docs-links`)
+- Docs local-link integrity (`poetry run poe docs-links`): scans all root-level `*.md` files and `docs/**/*.md`; exits 0 (success) when no broken links are found, exits 1 (failure) when broken links are detected; external URLs and anchor-only fragments are ignored; no dry-run mode
 - Mypy type-check (`poetry run poe typecheck`)
 - Unit/integration test matrix across Python 3.11-3.13
 - E2E suite job
diff --git a/scripts/check_markdown_links.py b/scripts/check_markdown_links.py
index 05e8061..ee7fbcb 100644
--- a/scripts/check_markdown_links.py
+++ b/scripts/check_markdown_links.py
@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
-"""Validate local markdown links in README and docs."""
+"""Validate local markdown links in repository root and docs."""
 
 from __future__ import annotations
 
@@ -8,7 +8,7 @@
 from dataclasses import dataclass
 from pathlib import Path
 
-LINK_PATTERN = re.compile(r"\[[^\]]+\]\(([^)]+)\)")
+LINK_PATTERN = re.compile(r"\[[^\]]+\]\(([^\s)]+)")
 IGNORED_PREFIXES = ("http://", "https://", "mailto:", "#")
 
 
@@ -19,7 +19,7 @@ class BrokenLink:
 
 
 def _candidate_markdown_files(repo_root: Path) -> list[Path]:
-    files = [repo_root / "README.md"]
+    files = list(repo_root.glob("*.md"))
     files.extend((repo_root / "docs").rglob("*.md"))
     return [file for file in files if file.exists()]