DSL Overview

The OOS DSL (Domain Specific Language) describes data contexts in XML. Each .ctx.xml file defines one or more contexts.

What is a Context?

A Context is the central data unit in OOS. It describes:

Which database table (or source) is used
Which fields are displayed
How data is formatted and presented
Which navigation is possible
Which rules the AI should follow when handling this data

Two Kinds of Context

collection

A collection is a list of records — equivalent to a multi-row SELECT.

<context name="person_list" kind="collection" source="person" dsn="demo"
         view="html/pages/person/person.table.html">
  <list_fields>id, firstname, lastname, email</list_fields>
  ...
</context>

Requires <list_fields> — defines which fields the AI queries
Typically renders a table

entity

An entity is a single record — equivalent to SELECT WHERE id = ?.

<context name="person_detail" kind="entity" source="person" dsn="demo"
         view="html/pages/person/person.detail.html">
  ...
</context>

No <list_fields> needed
Typically renders a detail form
Can have a gql_mutation (for updates)

File Structure

ctx/
  person.ctx.xml      ← person_list + person_detail
  note.ctx.xml        ← note_list + note_detail
  global.conf.xml     ← locales, global AI prompts
  infra.conf.xml      ← DSN definitions (backbone)

All .ctx.xml files in ctx_dir are automatically loaded on startup and merged into a single AST.

global.conf.xml

Contains locales and global AI instructions that apply to all contexts:

<oos>
  <ai>
    <prompt name="system">OOS is an AI-first enterprise data system...</prompt>
    <prompt name="query_behavior">Always use exactly the list_fields...</prompt>
  </ai>

  <locale name="standard"  language="de-DE" currency="EUR"/>
  <locale name="us_market" language="en-US" currency="USD"/>
</oos>