
E-commerce Listing Writer — Local Kit (Download)
E-commerce Listing Writer
What you're buying: a download package (skill instructions + a Python script) that runs on your own computer inside your own AI agent — it is not a cloud service.
You need: an AI agent that supports skills (e.g. Claude Code or Codex) — its subscription or API costs are yours; Python 3.9+ withopenpyxl.
Third-party services: none. The script works offline; your agent writes the copy from the product facts you give it.
Product facts in — compliant listings for 5 marketplaces out, with no made-up specs.
Platforms and fields
| Platform | What it writes |
|---|---|
| Amazon | Title (≤200, ≤80 recommended), 5 bullet points (CAPS LEAD: format), description, backend search terms (≤249 bytes) |
| Etsy | Title (≤140), 13 tags (≤20 chars each), description (first 160 chars work as the search snippet) |
| Shopify | Title, HTML body, tags, SEO title (≤70), meta description |
| Shopee | Title (≤120), sectioned description, specs and box contents, up to 18 hashtags |
| momo (Taiwan) | Short title (≤50), 3 feature points (≤40 each), formal spec description |
Languages: English and Traditional Chinese (Taiwan usage); other languages work too.
Example
3 products (a magnetic power bank, a handmade stoneware mug, a linen tote) → 12 listings for Shopee (Chinese + English), Amazon (English) and momo (Chinese).
- 6 errors were planted in the first draft, and the validator caught every one: "!" in an Amazon title, only 4 Amazon bullets, "free shipping" in a Shopee title, only 2 momo features, "Best" and "antibacterial" claims, and a made-up "20 hours" battery life (the product facts only said 20W).
- After fixes: 12 listings, 0 errors, 0 warnings.
- Output:
listings.xlsx(one sheet per platform), one CSV per platform and language, and a card preview page.
The preview page — one product, three marketplaces, every card validated:
Same facts, each platform's own format and length limits:
Try it — copy a prompt
- "Here's my products.csv — write Amazon and Etsy listings in English, and flag anything that needs proof."
- "Write a Shopify product page and SEO meta for this candle: 220 g soy wax, 45-hour burn, cedar & fig scent."
Why buy it
One payment, listings for your whole catalogue — no daily or monthly fees for a listing tool.
Who it's for
Marketplace sellers, Etsy makers, Shopify store owners, cross-border sellers and e-commerce assistants managing many SKUs.
Three automatic checks
- Platform rules: length limits, number of bullets and tags, banned title words ("free shipping", "sale", "Best Seller"…), Amazon's banned symbols, any word repeated more than twice.
- Risky or prohibited claims: medical claims (cure, weight loss, detox…), absolute guarantees (zero risk, lowest price…) and claims that need proof (antibacterial, organic, patented, eco-friendly…). English and Chinese lists, based on Amazon's restricted-claims policy, the FTC Green Guides and Taiwan's food, cosmetics and fair-trade rules.
- Made-up spec detection: every "number + unit" in the copy is checked against your product facts. If the facts say 20W but the copy says "20 hours", it gets flagged.
How it works
- Give the product facts (CSV, JSON or just tell your agent; the skill can create a blank template).
- Choose platforms and languages; the agent first builds keyword groups (main keyword + attributes, use cases, synonyms).
- The agent writes each listing, placing keywords where each platform weighs them.
- Validator → agent fixes → re-run, until 0 errors.
- Export to Excel, CSV and a preview page.
Output files
listings.xlsx— one sheet per platform, with a check-result column<platform>_<language>.csv— UTF-8 with BOM, opens cleanly in Excelpreview.html— card preview marked PASS / CHECK / FIX, filterable by platform
Requirements
- Python 3.9+ and
pip install openpyxl - Any AI agent client (Claude, Codex, etc.)
Limitations (please read)
- Copy is written by AI — check it before publishing.
- It only uses facts you provide: if information is missing, the agent asks you instead of filling gaps.
- The claim lists cover common risks but are not legal advice. Compliance with advertising law and platform policy is the seller's responsibility.
- Platform limits change and can vary by category or marketplace — check your seller centre (rules live in an editable
platform_rules.json). - Export columns follow common bulk-upload templates, but your account's official template may differ; paste the fields into the platform's own template.
- It does not publish listings, scrape competitor prices or provide live keyword search volume.
Files
SKILL.md— agent workflowscripts/listing_tool.py— template, validation and exportreferences/platform_rules.json— platform limits (editable)references/banned_claims.json— risky and prohibited claims (English and Chinese)references/writing-guide.md— keyword grouping and per-platform writing guide


