diff --git a/VERSION b/VERSION
index 0eed1a2..feaae22 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.12.0
+1.13.0
diff --git a/scripts/add_comment_marker.py b/scripts/add_comment_marker.py
new file mode 100644
index 0000000..11ced8b
--- /dev/null
+++ b/scripts/add_comment_marker.py
@@ -0,0 +1,51 @@
+"""Update the standards-version HTML comment marker in an agent file.
+
+Usage: python add_comment_marker.py <file_path> <new_version>
+
+Finds a line matching ``<!-- standards-version: X.Y.Z -->`` (anywhere in the
+file, though convention is the first line) and replaces the version.  Exits 0
+on success, 1 if the marker is absent.
+"""
+from __future__ import annotations
+
+import re
+import sys
+from pathlib import Path
+
+
+_MARKER_RE = re.compile(r"<!--\s*standards-version\s*:\s*[^\s>]+\s*-->")
+
+
+def _update(text: str, new_version: str) -> str | None:
+    """Return updated text, or None if no marker is found."""
+    new_marker = f"<!-- standards-version: {new_version} -->"
+    updated, count = _MARKER_RE.subn(new_marker, text, count=1)
+    return updated if count else None
+
+
+def main(argv: list[str]) -> int:
+    if len(argv) != 3:
+        print(f"usage: {argv[0]} <file_path> <new_version>", file=sys.stderr)
+        return 1
+
+    path = Path(argv[1])
+    new_version = argv[2]
+
+    try:
+        text = path.read_text(encoding="utf-8")
+    except OSError as exc:
+        print(f"error: cannot read {path}: {exc}", file=sys.stderr)
+        return 1
+
+    updated = _update(text, new_version)
+    if updated is None:
+        print(f"error: standards-version marker not found in {path}", file=sys.stderr)
+        return 1
+
+    path.write_text(updated, encoding="utf-8")
+    print(f"updated {path}")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv))
diff --git a/scripts/add_frontmatter.py b/scripts/add_frontmatter.py
new file mode 100644
index 0000000..bb05a96
--- /dev/null
+++ b/scripts/add_frontmatter.py
@@ -0,0 +1,65 @@
+"""Update the standards-version field in a YAML-frontmatter file.
+
+Usage: python add_frontmatter.py <file_path> <new_version>
+
+Finds the ``standards-version:`` key inside the leading ``---`` block and
+replaces its value.  Exits 0 on success, 1 if the marker is absent or the
+file cannot be parsed.
+"""
+from __future__ import annotations
+
+import re
+import sys
+from pathlib import Path
+
+
+_FRONTMATTER_RE = re.compile(r"\Astandardsversion:", re.I)  # loose sentinel
+
+
+def _update(text: str, new_version: str) -> str | None:
+    """Return updated text, or None if the standards-version key is absent."""
+    lines = text.splitlines(keepends=True)
+    in_block = False
+    for i, line in enumerate(lines):
+        stripped = line.lstrip()
+        if i == 0 and stripped.rstrip() == "---":
+            in_block = True
+            continue
+        if in_block and stripped.rstrip() in ("---", "..."):
+            break
+        if in_block and re.match(r"^standards-version\s*:", stripped):
+            lines[i] = re.sub(
+                r"(standards-version\s*:\s*).*",
+                rf"\g<1>{new_version}",
+                line,
+            )
+            return "".join(lines)
+    return None
+
+
+def main(argv: list[str]) -> int:
+    if len(argv) != 3:
+        print(f"usage: {argv[0]} <file_path> <new_version>", file=sys.stderr)
+        return 1
+
+    path = Path(argv[1])
+    new_version = argv[2]
+
+    try:
+        text = path.read_text(encoding="utf-8")
+    except OSError as exc:
+        print(f"error: cannot read {path}: {exc}", file=sys.stderr)
+        return 1
+
+    updated = _update(text, new_version)
+    if updated is None:
+        print(f"error: standards-version not found in frontmatter of {path}", file=sys.stderr)
+        return 1
+
+    path.write_text(updated, encoding="utf-8")
+    print(f"updated {path}")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv))