Compare AI tools

	Perplexity S	Symphony A	OpenRouter S	ChatGPT Operator B
Tagline	AI search done right. Cited answers, not chat theater.	OpenAI's open-source daemon that turns your Linear board into an always-on coding agent factory — tickets go in, pull requests come out.	One API, every model. Pay-as-you-go, no subscriptions.	OpenAI's browser agent. Clicks and types on websites for you.
Category	Research	Agents	Dev Platform	Agents
Pricing	Free + $20/mo Pro	Free (open-source)	Pay per token — model-dependent	Included with ChatGPT Pro $200/mo
Best for	Replacing Google for any question where you want a cited answer in seconds.	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 experimenting across models. Apps that want fallback logic.	Power users willing to pay $200/mo for a browser bot.
Strengths	Sources every claim Fast, current answers Pro Search runs multi-step research Spaces for persistent context	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	300+ models from one endpoint Automatic fallbacks between providers No subscription — just pay what you use	Actually uses websites — fills forms, clicks, checks out Built into ChatGPT Good for repetitive web tasks
Weaknesses	Not a general chatbot Answers can be shallow on complex topics	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	Slight markup over direct API Some provider features not exposed	Slow vs doing it yourself Breaks on complex auth flows $200/mo gate
Kai's verdict	S-tier for search. I use it before Google now. If you're still Googling everything, try this for a week.	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 for model-shopping. I use this for every prototype before committing.	B-tier. Still early. Manus is more flexible for less money.
Link	Open →	Open →	Open →	Open →