9router: what it is, what problem it solves & why it's gaining traction

What it solves

9Router is an AI router designed to reduce costs and prevent downtime for developers using AI coding tools. It solves the problem of hitting rate limits, wasting unused subscription quotas, and burning through tokens with verbose tool outputs (like git diff or ls) when using CLI-based AI agents.

How it works

It acts as a smart proxy between your AI coding tool (e.g., Claude Code, Cursor, Cline) and various AI providers. It provides an OpenAI-compatible API endpoint that handles:

• Token Compression: Uses RTK to compress tool results before they reach the LLM, saving 20-40% of input tokens.
• Tiered Fallback: Automatically routes requests through a priority list: Subscription $\rightarrow$ Cheap $\rightarrow$ Free providers, ensuring zero downtime.
• Format Translation: Translates requests and responses between different provider formats (e.g., OpenAI $\leftrightarrow$ Claude $\leftrightarrow$ Gemini).
• Quota Management: Tracks token usage and subscription resets in real-time.

Who it’s for

Developers who use AI-powered CLI tools and agents and want to optimize their API spend, maximize their existing subscriptions, or access free AI models without manually switching configurations.

Highlights

• RTK Token Saver: Lossless compression of tool outputs to reduce input token costs.
• Smart 3-Tier Fallback: Automatic switching between subscription, cheap, and free models to avoid rate limits.
• Ponytail & Caveman Modes: Prompt injection to force LLMs to be more terse and write minimal, YAGNI-first code, reducing output tokens.
• Universal Compatibility: Works with 40+ providers and 100+ models across major AI coding tools.
• Multi-Account Support: Round-robin load balancing between multiple accounts per provider.