Compare AI tools
Side-by-side: what they do, what they cost, what Kai actually thinks. Pass up to 4 tools via ?tools=claude,chatgpt,gemini.
Pick tools (4 selected)
Coding
Image
Productivity
Writing
Marketing
Devin A | Perplexity S | Grammarly A | HeyGen S | |
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| Tagline | Cognition Labs' autonomous coding engineer. | AI search done right. Cited answers, not chat theater. | Grammar check + tone + AI drafting, everywhere you type. | AI avatar videos. Record once, speak any language. |
| Category | Agents | Research | Writing | Video |
| Pricing | $500/mo | Free + $20/mo Pro | Free + $12-$15/mo Premium + team plans | Free + $24-$65/mo |
| Best for | Engineering teams offloading tickets. Ops/platform work. | Replacing Google for any question where you want a cited answer in seconds. | Non-native English writers, business email, anyone who types a lot. | Course creators, multilingual marketers, anyone scaling video content. |
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| Kai's verdict | A-tier for the right use case. Not for solo devs. If you manage engineers, try one license. | S-tier for search. I use it before Google now. If you're still Googling everything, try this for a week. | A-tier for non-native English speakers. B-tier if your English is already strong — Claude does better with tone. | S-tier for multilingual video. If you sell courses or speak at events, this is a cheat code. |
| Link | Open → | Open → | Open → | Open → |