Compare AI tools

	Symphony A	Claude Code S	Hume AI A	ChatGPT Operator B
Tagline	OpenAI's open-source daemon that turns your Linear board into an always-on coding agent factory — tickets go in, pull requests come out.	Anthropic's CLI agent. Opus-powered, operates on your repo directly.	Voice AI that reads + expresses emotion.	OpenAI's browser agent. Clicks and types on websites for you.
Category	Agents	Coding	Voice	Agents
Pricing	Free (open-source)	Part of Claude Pro/Max/Team plans	Free tier + pay-as-you-go	Included with ChatGPT Pro $200/mo
Best for	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.	Developers who want an agent, not autocomplete. Large refactors, tests, docs.	Therapy apps, customer service, any voice agent where emotion matters.	Power users willing to pay $200/mo for a browser bot.
Strengths	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	Runs locally, edits your actual files Strong on large codebases with 1M context Great at multi-step tasks	Detects + mirrors emotional tone EVI (Empathic Voice Interface) feels different Expressive voice output	Actually uses websites — fills forms, clicks, checks out Built into ChatGPT Good for repetitive web tasks
Weaknesses	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	Terminal-based — learning curve Can't be used without Claude subscription	Niche use case Pricing ramps fast	Slow vs doing it yourself Breaks on complex auth flows $200/mo gate
Kai's verdict	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.)	S-tier if you live in the terminal. Different shape than Cursor — complementary, not replacement.	A-tier in its niche. The only one that actually gets emotion right.	B-tier. Still early. Manus is more flexible for less money.
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