Compare AI tools

	OpenRouter S	Cursor TypeScript SDK A	Replicate S	Grammarly A
Tagline	One API, every model. Pay-as-you-go, no subscriptions.	Wire Cursor's full coding-agent runtime into your own apps, scripts, and CI/CD pipelines with a few lines of TypeScript.	Run any open-source AI model with an API call.	Grammar check + tone + AI drafting, everywhere you type.
Category	Dev Platform	Dev Platform	Dev Platform	Writing
Pricing	Pay per token — model-dependent	Token-based; requires Cursor plan (Pro from $20/mo). Composer 2 at $0.50/$2.50 per M tokens (in/out); fast variant $1.50/$7.50 per M tokens.	Pay per second of compute	Free + $12-$15/mo Premium + team plans
Best for	Developers experimenting across models. Apps that want fallback logic.	Engineering teams who already use Cursor and want to embed its coding-agent runtime into CI/CD pipelines, backend services, or internal developer tools without building agent infrastructure from scratch.	Developers using open-source models (Flux, SDXL, Whisper, etc).	Non-native English writers, business email, anyone who types a lot.
Strengths	300+ models from one endpoint Automatic fallbacks between providers No subscription — just pay what you use	Same runtime as the Cursor IDE — no reinventing sandboxing, context management, or model routing Three execution modes: local machine, Cursor cloud VMs (isolated per-agent), or self-hosted workers for air-gapped teams Cloud agents are durable — keep running even if your laptop sleeps or connection drops, and can open PRs automatically on finish Full harness included: codebase indexing, MCP servers, skills, hooks, and multi-agent delegation via subagents Visible in Cursor's Agents Window — programmatic runs can be inspected or taken over manually in the IDE	Tens of thousands of models (image, video, audio, LLMs) One-line API for any model Cog framework for custom model deploy	Works in every browser/app Now has generative AI (GrammarlyGO) Tone detection + suggestions
Weaknesses	Slight markup over direct API Some provider features not exposed	TypeScript-only SDK — no official Python or other language bindings at launch Public beta status means API surface and pricing can shift without much notice (Cursor has a track record of surprise pricing changes) Cloud VM costs layer on top of subscription credits, making cost estimation non-trivial at scale	Cold starts on less-popular models Pricing gets real at scale	Can feel naggy Premium features gate basics Privacy concerns (reads your writing)
Kai's verdict	S-tier for model-shopping. I use this for every prototype before committing.	If your team is already in the Cursor ecosystem, this is a genuinely compelling way to turn ad-hoc AI coding sessions into durable, automated workflows — but the beta label and Cursor's history with opaque pricing mean you'll want to set hard budget guardrails before going to production. (Verdict pending Phi's full review.)	S-tier for open-source model APIs. The default in this space.	A-tier for non-native English speakers. B-tier if your English is already strong — Claude does better with tone.
Link	Open →	Open →	Open →	Open →