Compare AI tools

	Perplexity S	Claude Code S	Claude Agent SDK S	Devin A
Tagline	AI search done right. Cited answers, not chat theater.	Anthropic's CLI agent. Opus-powered, operates on your repo directly.	Anthropic's SDK for building your own agents on Claude.	Cognition Labs' autonomous coding engineer.
Category	Research	Coding	Agents	Agents
Pricing	Free + $20/mo Pro	Part of Claude Pro/Max/Team plans	API usage + SDK is free	$500/mo
Best for	Replacing Google for any question where you want a cited answer in seconds.	Developers who want an agent, not autocomplete. Large refactors, tests, docs.	Developers building custom agents for their own company/product.	Engineering teams offloading tickets. Ops/platform work.
Strengths	Sources every claim Fast, current answers Pro Search runs multi-step research Spaces for persistent context	Runs locally, edits your actual files Strong on large codebases with 1M context Great at multi-step tasks	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
Weaknesses	Not a general chatbot Answers can be shallow on complex topics	Terminal-based — learning curve Can't be used without Claude subscription	Developer-only You build the UI	Expensive Best for well-scoped tasks Not for solo hobbyists
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 if you live in the terminal. Different shape than Cursor — complementary, not replacement.	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.
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