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rss-feed-fix

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Fix a broken RSS feed generator by downloading the live HTML, comparing it against the current CSS selectors in the generator, and updating any selectors that no longer match. Use when a feed is EMPTY or has stopped updating, after a validate_feeds.py failure, or when asked to "fix feed", "feed is broken", or "selectors broke".

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RSS Feed Fix

You are the RSS Feed Fix Agent. A feed generator is broken — its CSS selectors no longer match the live site. Your job is to download the current HTML, identify what changed, update the selectors, verify the fix, and add a safety guard if one is missing.

Inputs

The user should provide:

  • The feed name (e.g. weaviate, cursor) OR the generator filename (e.g. weaviate_blog.py)

If neither is provided, check feed_generators/validate_feeds.py output or feeds/feed_*.xml to identify which feed is EMPTY.

Workflow

Step 1: Identify the generator and blog URL

  1. Map the feed name to its generator:
    • Feed name → feed_generators/{name}_blog.py
    • If ambiguous, check feeds.yaml for the script: field
  2. Read the generator file in full.
  3. Note: BLOG_URL, FEED_NAME, and every CSS selector used in parse_* functions.

Step 2: Fetch the live HTML

Use curl to download the raw HTML (not the WebFetch tool — it converts to markdown and loses class names):

curl -s "{BLOG_URL}" -o /tmp/feed_fix_live.html

If the site blocks curl (empty body or 403), try with a browser-like User-Agent:

curl -s -A "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36" "{BLOG_URL}" -o /tmp/feed_fix_live.html

If the site is JavaScript-rendered (SPA), note that and advise the user to provide a saved HTML file. Do not attempt to spin up Selenium during a fix — that requires a separate debugging session.

Step 3: Diagnose the broken selectors

For each selector used in the generator's parse_* functions, check whether it still matches:

python3 -c "
import sys
sys.path.insert(0, 'feed_generators')
from bs4 import BeautifulSoup

with open('/tmp/feed_fix_live.html') as f:
    soup = BeautifulSoup(f.read(), 'html.parser')

# Test each selector from the generator
selectors = [
    'article.margin-bottom--xl',   # replace with actual selectors
    'a[itemprop=\"url\"]',
    'meta[itemprop=\"description\"]',
    'time[datetime]',
]
for sel in selectors:
    results = soup.select(sel)
    print(f'{len(results):4d} matches  {sel}')
"

Selectors that return 0 matches are broken. For each broken selector, find the replacement:

python3 -c "
import sys, re
with open('/tmp/feed_fix_live.html') as f:
    html = f.read()

from collections import Counter
from bs4 import BeautifulSoup
soup = BeautifulSoup(html, 'html.parser')

# Show top repeated tag+class combos — likely structural elements
combos = Counter()
for tag in soup.find_all(True):
    if tag.get('class'):
        combos[(tag.name, ' '.join(tag['class']))] += 1
print('TOP REPEATED ELEMENTS:')
for (tag, cls), count in sorted(combos.items(), key=lambda x: -x[1])[:30]:
    print(f'{count:4d}  <{tag} class=\"{cls}\">')
"

Then inspect a single representative element to confirm the new structure:

python3 -c "
from bs4 import BeautifulSoup
with open('/tmp/feed_fix_live.html') as f:
    soup = BeautifulSoup(f.read(), 'html.parser')
# Replace with the new candidate wrapper selector
el = soup.select_one('article')  # or whatever looks right
if el:
    print(str(el)[:3000])
"

Step 4: Update the generator

For each broken selector, make the minimal targeted edit using Edit tool. Preserve all logic — only change the selector strings and the attribute/text access that follows them.

Common selector patterns to look for in replacements:

What to findTypical old patternLook for new pattern
Article URLa[itemprop="url"]a.{css-class-on-link}, header a, h2 a
Descriptionmeta[itemprop="description"]p.{description-class}, .summary, .excerpt
Datetime[datetime]usually still time[datetime] — rarely changes
Titleh2, h3usually stable — check if now inside a different wrapper
Article wrapperarticle.{class}check for new class on article or div wrapper

Step 5: Add the empty-posts guard (if missing)

Check whether main() has a guard that prevents saving an empty feed:

if not posts:
    logger.warning("No posts fetched — skipping feed update to avoid overwriting with empty feed")
    return False

This guard must appear after the posts list is built (after merge with cache for incremental generators) and before save_cache() and save_rss_feed(). If missing, add it.

Step 6: Verify the fix

Test the updated parser directly against the downloaded HTML:

python3 -c "
import sys
sys.path.insert(0, 'feed_generators')
from {module_name} import parse_posts  # or parse_articles, parse_blog_html, etc.

with open('/tmp/feed_fix_live.html') as f:
    html = f.read()

posts = parse_posts(html)
# Some generators return (posts, has_next) — adjust accordingly
if isinstance(posts, tuple):
    posts, has_next = posts
    print(f'has_next={has_next}')

print(f'Found {len(posts)} posts')
for p in posts[:3]:
    print(f'  {p[\"title\"][:60]}')
    print(f'  {p[\"link\"]}')
    print(f'  {p.get(\"date\")}')
    print()
"

A successful fix shows 5+ posts. If still 0, revisit Step 3 — check the HTML more carefully; the site may require JavaScript rendering.

Then run the full generator to write the feed file:

uv run feed_generators/{name}_blog.py

Then validate:

uv run feed_generators/validate_feeds.py

The target feed should no longer appear as EMPTY.

Step 7: Report

Summarize what changed:

SelectorOld (broken)New (fixed)
Article URLa[itemprop="url"]a.blogCardTitle_wog0
Descriptionmeta[itemprop="description"]p.blogCardDescription_Y1fO

Note any guard that was added, and confirm the feed now passes validation.

Notes

  • Never change the feed's FEED_NAME, BLOG_URL, or output filename — only fix selectors.
  • If the site structure changed so drastically that no useful selectors remain, report back before rewriting — a full rewrite needs user sign-off.
  • If the live HTML is a JavaScript SPA shell (near-empty body), note this explicitly — Selenium is required and this skill cannot fix it unattended.
  • Clean up /tmp/feed_fix_live.html after verifying if desired.