Compare AI tools

	Perplexity S	Claude Agent SDK S	ChatGPT Operator B	Gemini A
Tagline	AI search done right. Cited answers, not chat theater.	Anthropic's SDK for building your own agents on Claude.	OpenAI's browser agent. Clicks and types on websites for you.	Google's answer. Best integrated with Workspace + free for a lot.
Category	Research	Agents	Agents	Chatbots
Pricing	Free + $20/mo Pro	API usage + SDK is free	Included with ChatGPT Pro $200/mo	Free + $20/mo Advanced (bundled with 2TB Drive)
Best for	Replacing Google for any question where you want a cited answer in seconds.	Developers building custom agents for their own company/product.	Power users willing to pay $200/mo for a browser bot.	Anyone already on Google, research tasks, summarizing long documents.
Strengths	Sources every claim Fast, current answers Pro Search runs multi-step research Spaces for persistent context	Production-grade agent primitives Built on Claude (best reasoning) Full control — build exactly what you need	Actually uses websites — fills forms, clicks, checks out Built into ChatGPT Good for repetitive web tasks	Native Google Workspace integration Very long context (1M+) Deep Research feature Free tier is generous
Weaknesses	Not a general chatbot Answers can be shallow on complex topics	Developer-only You build the UI	Slow vs doing it yourself Breaks on complex auth flows $200/mo gate	Writing quality trails Claude Over-refusals on edge content UI is cluttered
Kai's verdict	S-tier for search. I use it before Google now. If you're still Googling everything, try this for a week.	S-tier for builders. The right primitives. What Kai is built on under the hood.	B-tier. Still early. Manus is more flexible for less money.	A-tier. The Deep Research feature is genuinely useful. Don't sleep on it if you're already paying Google.
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