BAML

What Is Boundary?

Boundary is an open-source framework designed to make AI applications type-safe, reliable, and production-ready. Its core technology, BAML (Boundary Markup Language), is a domain-specific language for defining and managing interactions with large language models.

With BAML, developers can create structured, predictable, and validated AI pipelines that generate consistent outputs across different programming languages. Boundary eliminates ambiguity in prompt design, improves reliability, and integrates easily with modern development workflows.

How To Use Boundary

Boundary can be installed through the command line using npm or pip, and configured within your existing codebase. Developers use BAML files to declare prompt functions, input schemas, and expected output structures. Once defined, the Boundary compiler automatically generates strongly typed code for Python, TypeScript, Ruby, or Go.

This approach ensures that every AI interaction is validated before runtime. BAML integrates seamlessly with testing frameworks and CI/CD pipelines, making it easy to maintain correctness as applications scale. Boundary also supports retries, fallbacks, and local testing to improve resilience in production environments.

Boundary Key Features

• Type-Safe AI Pipelines: Define inputs, outputs, and validations for every AI function.
• Cross-Language Code Generation: Automatically produce type-safe client code in Python, TypeScript, Ruby, or Go.
• Schema Enforcement: Ensure model outputs follow exact data structures without manual validation.
• Error Handling and Retries: Add built-in mechanisms for retries, timeouts, and fallback logic.
• Testing and CI/CD Integration: Validate LLM behavior during continuous integration and deployment.
• Prompt Functions: Declare reusable prompt templates with well-defined parameters.
• Developer Productivity: Simplify collaboration between engineers, data scientists, and product teams.
• Open Source and Extensible: Fully open-source with an active developer community and regular updates.

Boundary Use Cases

• AI Agent Development: Build reliable, schema-validated agents that perform multi-step reasoning and actions.
• Data Extraction and Structuring: Guarantee consistent, structured output from text, PDFs, or documents.
• Enterprise Automation: Enforce predictable model responses for compliance and auditability.
• API Integration: Create consistent interfaces between LLMs and back-end systems.
• Content Generation: Ensure formatted, validated outputs for reports, marketing materials, and summaries.
• Developer Tooling: Maintain strict data contracts between LLMs and your application codebase.

Boundary FAQ

Is Boundary free or paid?
Boundary and BAML are fully open-source and free to use. Enterprise support and advanced integrations may be available in the future.

What programming languages does Boundary support?
Boundary supports automatic code generation for Python, TypeScript, Ruby, and Go.

Can Boundary work with any LLM?
Yes. Boundary is model-agnostic and can connect to OpenAI, Anthropic, Gemini, or any API that supports text-based generation.

Does Boundary store user data?
No. Boundary does not store or process user data. It provides a framework that runs within your development environment.

Can I use Boundary in production systems?
Yes. Boundary is designed for reliability, validation, and deployment in production AI pipelines.

Why We Featured Boundary on Add AI Agents

At Add AI Agents, we highlight technologies that make AI more reliable, transparent, and developer-friendly. Boundary stands out for solving one of the most common challenges in AI development: unpredictable model outputs. By introducing BAML, a type-safe language for building structured AI workflows, Boundary gives developers the control and confidence needed to deploy AI systems that are robust, testable, and production-ready.