CostLens SDK v2.0.0

Smart AI cost optimization for OpenAI and Anthropic. Automatically routes expensive models to cheaper alternatives while maintaining quality. Save up to 40% on AI API costs with zero code changes.

Quick Start

import { CostLens } from 'costlens';
import OpenAI from 'openai';

const costlens = new CostLens({
  apiKey: 'cl_your_key_here' // Get yours at costlens.dev/settings
});
const openai = new OpenAI({ apiKey: 'your-openai-key' });
const ai = costlens.wrapOpenAI(openai);

const response = await ai.chat.completions.create({
  model: 'gpt-4',
  messages: [{ role: 'user', content: 'Hello!' }],
});
// → Automatically routed to cheaper model when quality allows

Features

• Smart Model Routing: GPT-4 → GPT-4.1-nano, Claude Opus → Claude Haiku
• Quality Protection: Prevents routing when quality would degrade
• Zero Code Changes: Drop-in wrapper for existing OpenAI/Anthropic code
• Cost Analytics: Track usage, costs, and savings per feature/developer
• Token Tracking: See where every token goes and what it ships
• Caching: Avoid duplicate API calls with intelligent caching
• Kill Switch: Auto-pause runaway agents, burst detection
• Fallback Support: Automatic fallback to alternative models

Installation

npm install costlens

Setup

1. Sign up at costlens.dev
2. Get your API key from Settings
3. Wrap your OpenAI or Anthropic client:

import { CostLens } from 'costlens';
import OpenAI from 'openai';

const costlens = new CostLens({
  apiKey: process.env.COSTLENS_API_KEY!,
});

// OpenAI
const openai = costlens.wrapOpenAI(new OpenAI());

// Anthropic
import Anthropic from '@anthropic-ai/sdk';
const anthropic = costlens.wrapAnthropic(new Anthropic());

Configuration

const costlens = new CostLens({
  apiKey: 'cl_...', // Required
  baseUrl: 'https://api.costlens.dev', // Default
  smartRouting: true, // Auto-route to cheaper models
  enableCache: true, // Cache identical requests
  logLevel: 'warn', // silent | error | warn | info
});

Pricing

The SDK requires a CostLens subscription:

• Pro ($49/mo): Smart routing, cost analytics, caching
• Business ($149/mo): + token tracking, kill switch, per-feature attribution

Start a 14-day free trial at costlens.dev.

Links

• Documentation
• Dashboard
• Pricing
• GitHub