Ax

What is Ax?

Ax is a programming framework for building LLM applications and agents from typed signatures instead of manually assembling prompts and parsing loosely structured output. Developers define the expected inputs and outputs, and Ax handles model calls, validation, streaming, and optimization around that contract.

The project supports TypeScript, Python, Java, C++, Go, and Rust. It is positioned for applications that need reliable structured results and for agents that combine reasoning with programmatic tools while preserving language-native development workflows.

Core Features

• Typed signatures: Defines model inputs and outputs as program contracts.
• Output validation: Checks generated results against the expected structure.
• Streaming: Supports incremental model responses.
• Optimization: Improves prompts and model behavior around declared signatures.
• Multi-language support: Provides native workflows across six listed programming languages.
• Agent development: Supports LLM and reasoning-agent applications rather than only one-off prompts.

Use Cases

• Structured extraction: Developers convert unstructured model responses into validated application data.
• LLM application development: Teams build model-backed features with typed interfaces.
• Agent tools: Engineers connect reasoning agents to programmatic functions and services.
• Cross-language systems: Organizations use a consistent model-programming approach across multiple stacks.

Frequently Asked Questions

Which languages does Ax support?

The website lists TypeScript, Python, Java, C++, Go, and Rust.

Does Ax validate model output?

Yes. Validation is one of the capabilities named in its product description.

Is Ax only for prompt templates?

No. It is presented as a framework for reliable LLM calls and agent development based on typed signatures.