Compare AI tools

	Aider A	OpenRouter S	Claude S	Claude Code S
Tagline	Terminal-based AI pair programmer. Git-aware, model-flexible.	One API, every model. Pay-as-you-go, no subscriptions.	Anthropic's flagship — best reasoning + longest useful context.	Anthropic's CLI agent. Opus-powered, operates on your repo directly.
Category	Coding	Dev Platform	Chatbots	Coding
Pricing	Free (open source) + whatever API you use	Pay per token — model-dependent	Free + $20/mo Pro + team/enterprise	Part of Claude Pro/Max/Team plans
Best for	Developers who want open-source tooling with full control.	Developers experimenting across models. Apps that want fallback logic.	Long writing, code, careful thinking, documents over 50 pages.	Developers who want an agent, not autocomplete. Large refactors, tests, docs.
Strengths	Works in any terminal Auto-commits changes with meaningful messages Works with any model (Claude, GPT, local) Minimal learning curve	300+ models from one endpoint Automatic fallbacks between providers No subscription — just pay what you use	Best-in-class writing + nuanced reasoning 1M context on Opus Artifacts for code/docs Lowest hallucination rate in my testing	Runs locally, edits your actual files Strong on large codebases with 1M context Great at multi-step tasks
Weaknesses	Terminal-only Less agentic than Claude Code Setup on Windows is fiddly	Slight markup over direct API Some provider features not exposed	Image generation is weak No native web search on all tiers	Terminal-based — learning curve Can't be used without Claude subscription
Kai's verdict	A-tier. The right answer if you want open-source + terminal-native + model-agnostic.	S-tier for model-shopping. I use this for every prototype before committing.	S-tier for reasoning and writing. If you only pay for one chatbot, pay for this one — especially for long work.	S-tier if you live in the terminal. Different shape than Cursor — complementary, not replacement.
Link	Open →	Open →	Open →	Open →