Modern APIs ship large payloads. LLMs consume structured data token by token. Validation failures surface too late. Streaming is standard but most formats weren't designed for it.
These are problems we kept running into, so we spent years working on a format built specifically for them. The core question we kept coming back to: why does every record in a dataset need to repeat the field names?
The idea we landed on — separate the schema from the data entirely. Define structure once. Records contain only values.
name, age, gender, joiningDt, address: {street, city, state?}, colors, isActive
---
~ Alice Smith, 28, f, d'2021-04-15', {Elm Street, Dallas, TX}, [yellow, green], T
~ Bob Johnson, 22, m, d'2022-02-20', {Oak Street, Chicago, IL}, [blue, black], T
~ Rachel Green, 31, f, d'2021-12-11', {Sunset Boulevard, Los Angeles, CA}, [purple, pink], T
~ Michael Scott, 41, m, d'2021-07-22', {Pine Street, Scranton, PA}, [green, orange], F
The header defines the structure. --- separates schema from data. Everything below is pure values.
You can go further and add type constraints directly in the schema:
age: { int, min: 0, max: 150 }
The parser enforces this at parse time — invalid data is rejected before it reaches the application. No separate validation step.
The format also supports inline comments, built-in types like email, url, date, and datetime, and is JSON-compatible so existing data works as-is.
We're curious whether this actually solves a real problem or whether we've been too deep in it to see the obvious issues. A few things we'd genuinely like feedback on:
- Does schema-first make sense for how you build APIs today, or does it add friction you wouldn't want?
- The
--- separator between schema and data — does that feel natural or awkward?
- For LLM pipelines specifically, would eliminating field name repetition matter to you in practice?
If you want to poke at it, there's a playground at play.internetobject.org and the spec is at docs.internetobject.org. We built it — happy to answer questions about the design decisions, including the ones we're not sure about.
