Compare AI tools

	GitHub Copilot B	Windsurf A	Cartesia S	Khanmigo S
Tagline	Microsoft/GitHub's autocomplete. Deep VS Code + JetBrains integration.	Codeium's agentic IDE. Cascade agent + strong free tier.	Ultra-low-latency voice. Built for realtime agents.	Khan Academy's AI tutor. Socratic method, built for learning.
Category	coding	coding	voice	education
Pricing	Free (limited) + $10/mo Pro + $19/mo Business	Free + $15/mo Pro	Free tier + usage-based API	$4/mo (free for teachers)
Best for	Teams with GitHub already. Devs who don't want to change IDEs.	Developers who want Cursor-like power for less money.	Developers building voice agents, phone bots, interactive apps.	Students K-12. Parents helping with homework. Teachers prepping lessons.
Strengths	Great enterprise story Works in your existing IDE Chat + autocomplete	Cheaper than Cursor Cascade agent for multi-file tasks Solid free tier	< 90ms latency — the fastest in the market Sonic model sounds natural Developer-friendly API	Socratic — doesn't give answers, asks questions Trusted by schools + parents Integrated with Khan Academy curriculum
Weaknesses	Less agentic than Cursor/Claude Code Model quality varies	Smaller community Model selection more limited	Fewer voices than ElevenLabs Less consumer-facing brand	K-12 focus (not deep for adults) Slower than general chatbots
Kai's verdict	B-tier. Solid for autocomplete but the category moved past it. Pick Cursor unless you can't.	A-tier. Close second to Cursor. If $5/mo matters, start here.	S-tier for realtime. If latency matters more than voice catalog, start here.	S-tier for kids learning. The tutoring UX is legit — not a generic chatbot dressed up.
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