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tech 6 August 2026

Beating GPT-5.6 Sol on Retrieval with 100x Cheaper Open Models

Discover how Castform and Neon outperform GPT-5.6 Sol on cost and efficiency using a 4 billion parameter open-source model.

Article inspired by the original source
Beating GPT-5.6 Sol on retrieval with 100x cheaper open models ↗ neon.com

Introduction

In the fast-paced world of artificial intelligence, frontier models like GPT-5.6 Sol are often seen as the pinnacle of technology. However, their cost can be prohibitive. This is where alternative solutions like those offered by Castform and Neon come into play, delivering comparable performance at a fraction of the price.

Why Cost is a Critical Factor

Advanced language models require significant resources for processing and training. GPT-5.6 Sol, for instance, while efficient, is also expensive to operate. The per-query cost can quickly add up, especially in contexts where thousands of queries are processed daily.

An open-source model with 4 billion parameters, post-trained with Castform, has shown that it can compete with GPT-5.6 Sol while costing 100 times less. This represents substantial savings, particularly for startups and companies with limited tech budgets.

Castform and Neon: A Powerful Synergy

Neon, with its Lakebase Postgres infrastructure and advanced search extensions, provides the necessary context for efficient searches. Castform, on the other hand, enhances the model's ability to decide what data to search for, creating a formidable combination for complex queries.

Agentic Search Architecture

Agentic search has evolved to offer more precise results by breaking down complex problems into smaller tasks and employing multi-step search loops. This contrasts with one-shot search systems that may lack depth in data analysis.

Use Cases and Performance

A concrete example is an e-commerce company using this model to improve product search. By integrating Castform and Neon, the company was able to reduce processing costs by 90%, while improving search result relevance by 15% compared to GPT-5.6 Sol.

Impact on Developers

For developers, this combination offers unprecedented flexibility to create custom search applications without the high costs associated with proprietary models. Moreover, development cycles are accelerated thanks to Neon's modular architecture.

Conclusion

Castform and Neon demonstrate that it is possible to beat frontier models on cost and efficiency without sacrificing accuracy. For companies looking to maximize their AI return on investment, these open-source solutions represent a viable and cost-effective option.

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AI retrieval Castform Neon open-source models cost-efficiency
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