"""Validity reward: checks HTML parseability and structural completeness."""
from __future__ import annotations
from openenv.server.rewards import extract_html
# Minimum unique tags to consider "diverse" content (8 matches docstring intent)
_MIN_DIVERSE_TAGS = 8
def html_validity_reward(completions: list[list[dict]]) -> list[float]:
"""Score HTML validity on a scale of 0.0–1.0.
Checks:
- Parses without crashing (required)
- Has , , structural tags (0–0.5)
- Has diverse tag usage (≥8 unique tag types) (0–0.5)
Args:
completions: List of completion message lists.
Returns:
List of float scores in [0.0, 1.0].
"""
from bs4 import BeautifulSoup
results = []
for completion in completions:
content = completion[0]["content"]
html = extract_html(content)
try:
soup = BeautifulSoup(html, "html.parser")
has_html = soup.find("html") is not None
has_head = soup.find("head") is not None
has_body = soup.find("body") is not None
structure_score = (int(has_html) + int(has_head) + int(has_body)) / 3.0
all_tags = [t.name for t in soup.find_all() if t.name]
unique_tags = len(set(all_tags))
diversity_score = min(unique_tags / _MIN_DIVERSE_TAGS, 1.0)
score = 0.5 * structure_score + 0.5 * diversity_score
except Exception:
score = 0.0
results.append(score)
return results