Hover
IDE style hover documentation on any webpage
Details
- External ID
- 46490895
- Source
- HN
- Company
- —
- Product
- Hover
- Website domain
- github.com
- Launched
- Jan. 4, 2026
- Cohort
- —
- Upvotes
- 58
- Upvotes percentile
- 0.8293807641633728
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:25 p.m.
- Updated at
- Sept. 7, 2026, 9:25 p.m.
Description
I thought it would be interesting to have ID style hover docs outside the IDE.Hover is a Chrome extension that gives you IDE style hover tooltips on any webpage: documentation sites, ChatGPT, Claude, etc.How it works: - When a code block comes into view, the extension detects tokens and sends the code to an LLM (via OpenRouter or custom endpoint) - The LLM generates documentation for tokens worth documenting, which gets cached - On hover, the cached documentation is displayed instantlyA few things I wanted to get right: - Website permissions are granular and use Chrome's permission system, so the extension only runs where you allow it - Custom endpoints let you skip OpenRouter entirely – if you're at a company with its own infra, you can point it at AWS Bedrock, Google AI Studio, or whatever you haveBuilt with TypeScript, Vite, and the Chrome extension APIs. Coming to the Chrome Web Store soon.Would love feedback on the onboarding experience and general UX – there were a lot of design decisions I wasn't sure about.Happy to answer questions about the implementation.
Enrichment
- Theme
- markdown editors and writing tools
- Vertical
- Horizontal
- Function
- Dev tools
- Audience
- Developer
- AI stance
- Not AI
- Project type
- Hobby / open-source project
- Normalized one-liner
- hover documentation for webpages
- Manually corrected
- False
Could you build this?
Yes A Chrome extension that parses code tokens in web page pre/code blocks and queries documentation or an LLM to show hover tooltips can be readily built with AI assistance.
Discussion
20 comments analyzed.
Competitors mentioned: Firefox built-in link previews with AI, VSCode documentation tooltip plugins, Language servers (LSP), cht.sh (cheat sheet wiki)
Concerns raised: LLM hallucinations produce false/inaccurate information, Generated explanations invent methods and parameters that don't exist, Outdated documentation causes confusion across software versions, Impractical to maintain universal token-to-documentation mappings, Scaling beyond single language ecosystem is difficult
Feature requests: Delay documentation fetch until code block visible for n milliseconds to avoid throttling, Track code block mutations (for streamed responses like ChatGPT) before generating docs, Use tree-sitter or similar for accurate token parsing without hallucinations, Fetch official docs mapped to actual code version being viewed, Make "tooltips" terminology more prominent in UI
Competitors
Other products that read as similar to this one — 56 launches clear the similarity bar, closest 8 shown.
Attention rank: #8 of 57 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 21 days after the earliest competitor.
- I made a Tailwind alternative for Preact · hn · 2026-01-11 · 6 upvotes · similarity 0.41
- Chrome extension that extracts styles and generates DESIGN.md files · hn · 2026-04-15 · 6 upvotes · similarity 0.39
- Sider Code · ph · 2026-09-01 · 232 upvotes · similarity 0.39
- Selector Forge · hn · 2026-06-22 · 38 upvotes · similarity 0.37
- Markdown Reader · ph · 2026-09-26 · 1 upvotes · similarity 0.37
- Cursor for Userscripts · hn · 2026-01-28 · 56 upvotes · similarity 0.37
- domscout · ph · 2026-09-25 · 1 upvotes · similarity 0.37
- Google Chrome Vertical Tabs · ph · 2026-04-08 · 377 upvotes · similarity 0.37
Other launches for this product
Same idea, different domain
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