Compare AI tools

	Hume AI A	Symphony A	GitHub Copilot B	Perplexity S
Tagline	Voice AI that reads + expresses emotion.	OpenAI's open-source daemon that turns your Linear board into an always-on coding agent factory — tickets go in, pull requests come out.	Microsoft/GitHub's autocomplete. Deep VS Code + JetBrains integration.	AI search done right. Cited answers, not chat theater.
Category	Voice	Agents	Coding	Research
Pricing	Free tier + pay-as-you-go	Free (open-source)	Free (limited) + $10/mo Pro + $19/mo Business	Free + $20/mo Pro
Best for	Therapy apps, customer service, any voice agent where emotion matters.	Engineering teams already using Linear + OpenAI Codex who want to stop babysitting agent sessions and instead let the issue tracker drive autonomous coding at scale.	Teams with GitHub already. Devs who don't want to change IDEs.	Replacing Google for any question where you want a cited answer in seconds.
Strengths	Detects + mirrors emotional tone EVI (Empathic Voice Interface) feels different Expressive voice output	Fully autonomous ticket-to-PR pipeline: every open Linear issue gets its own isolated Codex agent without manual supervision Fault-tolerant Elixir/OTP architecture automatically restarts crashed agents and manages hundreds of concurrent runs WORKFLOW.md keeps all orchestration policy version-controlled inside the repo, so agent behavior is reproducible and reviewable like code Proven internal results: OpenAI reported a 500% increase in landed PRs on some teams within three weeks Open spec encourages community re-implementations in any language, not just Elixir	Great enterprise story Works in your existing IDE Chat + autocomplete	Sources every claim Fast, current answers Pro Search runs multi-step research Spaces for persistent context
Weaknesses	Niche use case Pricing ramps fast	Currently only supports Linear as an issue tracker — GitHub Issues and Jira integrations are not yet official Only OpenAI Codex is officially supported as the agent runtime; other model integrations are community-contributed and incomplete Self-hosted, Elixir-dependent engineering preview with no built-in sandboxing — not suitable for untrusted or production environments out of the box	Less agentic than Cursor/Claude Code Model quality varies	Not a general chatbot Answers can be shallow on complex topics
Kai's verdict	A-tier in its niche. The only one that actually gets emotion right.	Symphony is the most architecturally serious 'issue tracker as control plane' approach yet — 15K GitHub stars in weeks confirms the idea resonates — but it's still a rough, self-hosted engineering preview that demands Elixir chops and a Linear-only workflow. (Verdict pending Phi's full review.)	B-tier. Solid for autocomplete but the category moved past it. Pick Cursor unless you can't.	S-tier for search. I use it before Google now. If you're still Googling everything, try this for a week.
Link	Open →	Open →	Open →	Open →