BAML
Apache-2.0 typed DSL for LLM functions — schema-guaranteed outputs
AI Agents / Agents · Apache-2.0 · 9.4k
Reviewed 2026-09-29 · last push 2026-10-18 · repo checked 2026-10-19
What's Good
Apache-2.0 (BoundaryML/baml). DSL + codegen for structured LLM functions with schema-guaranteed outputs, streaming, and multi-provider backends. Docs at docs.boundaryml.com; playground and VS Code tooling. Cloud/Boundary product is optional — language and runtime are OSS. ★9,350 on GitHub 2026-09-29.
The Catch
Vs Instructor / PydanticAI / Vercel AI SDK structured outputs: those stay inside Python/TS; BAML is a separate DSL + compiler you adopt for schema-first agent I/O. Pre-1.0 energy — APIs and tooling still move; Boundary Cloud pricing is a separate lane from the Apache core.
Verdict
Apache-2.0 schema-first LLM DSL when typed agent I/O beats prompt+parse — not Instructor-in-Python, not a hosted-only agent platform.
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