AI is powerful, but inefficient prompts and poorly managed context are costing you time, money, and trust. fenn is the backend that not only auto-optimizes your prompts, but also engineers the right context for every LLM call.
Building with LLMs like GPT or Claude? You're likely facing:
Inefficient prompts and bloated context windows waste tokens and drive up API bills—up to 79% of inference costs could be saved with optimization.
Unreliable outputs happen when the model lacks the right context, leading to errors and lost trust. Global costs hit $67B in 2024 alone.
Manual tweaking and verification slow down your team, reducing efficiency by 22%.
As your app grows, managing context across users, sessions, and workflows becomes a bottleneck for both performance and reliability.
Prompt engineering is just the start. The real challenge—and opportunity—is in context engineering : delivering the right information, memory, and data to your LLMs at the right time.
fenn is a simple backend SDK and API that integrates with your code to manage, optimize, and track AI prompts—and now, the full context your models need to perform at their best.
Asynchronously test and refine prompts on cheaper models, generating versions that cut costs by up to 79% while maintaining output quality.
Dynamically build and compress the right context for every LLM call—combining user history, retrieved documents, and business rules.
Real-time monitoring of token usage, executions, and savings—never overpay for AI again.
Inject only verified, relevant data—reducing hallucinations by up to 68% and boosting output reliability.
Works with OpenAI, Anthropic, and more. Just pass your prompt or context ID, and get optimized results.
Multi-tenant support with API keys for teams, powered by secure auth like Clerk.
fenn is your bridge from prompt engineering to full context engineering—helping you build AI that's cheaper, smarter, and actually works in production.
Be the first to try fenn and validate if this solves your AI challenges. Sign up now—no commitment, just priority access and updates.
We'll notify you when beta launches.