Compare AI tools

	Perplexity S	Claude Agent SDK S	Devin A	Cursor S
Tagline	AI search done right. Cited answers, not chat theater.	Anthropic's SDK for building your own agents on Claude.	Cognition Labs' autonomous coding engineer.	VS Code fork that made AI coding actually work.
Category	Research	Agents	Agents	Coding
Pricing	Free + $20/mo Pro	API usage + SDK is free	$500/mo	Free + $20/mo Pro + $40/mo Business
Best for	Replacing Google for any question where you want a cited answer in seconds.	Developers building custom agents for their own company/product.	Engineering teams offloading tickets. Ops/platform work.	Developers. Non-developers who want to ship working code.
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	Works like an engineer — takes Slack tasks, opens PRs Handles multi-hour engineering work Reports back with what it did	Tab completion feels like mind-reading Composer for multi-file edits Runs Claude, GPT, Gemini — you pick
Weaknesses	Not a general chatbot Answers can be shallow on complex topics	Developer-only You build the UI	Expensive Best for well-scoped tasks Not for solo hobbyists	Can feel overwhelming for non-coders Expensive at scale
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.	A-tier for the right use case. Not for solo devs. If you manage engineers, try one license.	S-tier for coding. If you write code of any kind, this pays back the $20 in a day.
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