Compare AI tools

	Symphony A	OpenRouter S	GitHub Copilot B	Cline A
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.	One API, every model. Pay-as-you-go, no subscriptions.	Microsoft/GitHub's autocomplete. Deep VS Code + JetBrains integration.	Open-source VS Code agent. Reads + writes + runs.
Category	Agents	Dev Platform	Coding	Coding
Pricing	Free (open-source)	Pay per token — model-dependent	Free (limited) + $10/mo Pro + $19/mo Business	Free (open source) + your API costs
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 experimenting across models. Apps that want fallback logic.	Teams with GitHub already. Devs who don't want to change IDEs.	VS Code users who want agentic coding without changing IDEs.
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	300+ models from one endpoint Automatic fallbacks between providers No subscription — just pay what you use	Great enterprise story Works in your existing IDE Chat + autocomplete	Free extension for VS Code Plan + Act modes Model-agnostic (Claude, GPT, local) Sees terminal output and iterates
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	Slight markup over direct API Some provider features not exposed	Less agentic than Cursor/Claude Code Model quality varies	Can burn tokens fast if not watched Less polished than Cursor
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 for model-shopping. I use this for every prototype before committing.	B-tier. Solid for autocomplete but the category moved past it. Pick Cursor unless you can't.	A-tier. Best free agentic option in VS Code. Use with Claude for best results.
Link	Open →	Open →	Open →	Open →