ci(docs): add markdown relative link check gate

.github/workflows/ci.yml

@@ -87,6 +87,11 @@ jobs:
           make frontend-test
           make frontend-build
 
+
+      - name: Docs link check
+        run: |
+          python scripts/check_markdown_links.py
+
       - name: Upload coverage artifacts
         if: always()
         uses: actions/upload-artifact@v4

Makefile

@@ -122,3 +122,8 @@ backend-templates-sync: ## Sync templates to existing gateway agents (usage: mak
 
 .PHONY: check
 check: lint typecheck backend-coverage frontend-test build ## Run lint + typecheck + tests + coverage + build
+
+
+.PHONY: docs-link-check
+docs-link-check: ## Check for broken relative links in markdown docs
+	python scripts/check_markdown_links.py

scripts/check_markdown_links.py

@@ -0,0 +1,92 @@
+#!/usr/bin/env python3
+"""Lightweight markdown link checker for repo docs.
+
+Checks *relative* links inside markdown files and fails CI if any targets are missing.
+
+Design goals:
+- No external deps.
+- Ignore http(s)/mailto links.
+- Ignore pure anchors (#foo).
+- Support links with anchors (./path.md#section) by checking only the path part.
+
+Limitations:
+- Does not validate that anchors exist inside target files.
+- Does not validate links generated dynamically or via HTML.
+"""
+
+from __future__ import annotations
+
+import re
+import sys
+from pathlib import Path
+
+
+LINK_RE = re.compile(r"\[[^\]]+\]\(([^)]+)\)")
+
+
+def iter_md_files(root: Path) -> list[Path]:
+    patterns = [
+        root / "README.md",
+        root / "CONTRIBUTING.md",
+    ]
+    files: list[Path] = []
+    for p in patterns:
+        if p.exists():
+            files.append(p)
+    docs = root / "docs"
+    if docs.exists():
+        files.extend(sorted(docs.rglob("*.md")))
+    return files
+
+
+def normalize_target(raw: str) -> str | None:
+    raw = raw.strip()
+    if not raw:
+        return None
+    if raw.startswith("http://") or raw.startswith("https://") or raw.startswith("mailto:"):
+        return None
+    if raw.startswith("#"):
+        return None
+    # strip query/fragment
+    raw = raw.split("#", 1)[0].split("?", 1)[0]
+    if not raw:
+        return None
+    return raw
+
+
+def main() -> int:
+    root = Path(__file__).resolve().parents[1]
+    md_files = iter_md_files(root)
+
+    missing: list[tuple[Path, str]] = []
+
+    for md in md_files:
+        text = md.read_text(encoding="utf-8")
+        for m in LINK_RE.finditer(text):
+            target_raw = m.group(1)
+            target = normalize_target(target_raw)
+            if target is None:
+                continue
+
+            # Skip common markdown reference-style quirks.
+            if target.startswith("<") and target.endswith(">"):
+                continue
+
+            # Resolve relative to current file.
+            resolved = (md.parent / target).resolve()
+            if not resolved.exists():
+                missing.append((md, target_raw))
+
+    if missing:
+        print("Broken relative links detected:\n")
+        for md, target in missing:
+            print(f"- {md.relative_to(root)} -> {target}")
+        print(f"\nTotal: {len(missing)}")
+        return 1
+
+    print(f"OK: checked {len(md_files)} markdown files")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())