Extension Mechanisms

MRS provides explicit extension mechanisms to support additional domains while keeping a stable core. See: /MRS-Specification-RFC#15-extension-mechanisms

Custom Properties

Events, spans, and directions support custom properties with the x- prefix:

(: 0 C4.q 
  :id #uuid "..."
  :dyn f
  :x-source "manuscript-page-47"
  :x-confidence 0.85
  :x-variant "A")

Custom properties:

MUST begin with x-
MUST have string, number, boolean, or array values
SHOULD be documented by the creating system
MAY be ignored by systems that don’t recognize them

Note: The :at field is not shown above because it is a derived field computed by the orchestrator, not provided by agents.

Namespace Extensions

For complex extensions, use namespaced properties:

(: 0 C4.q
  :id #uuid "..."
  :analysis:roman-numeral "I"
  :analysis:function "tonic"
  :mei:xml-id "note-001")

Registered Namespaces

Namespace	Purpose
`x-*`	Unregistered extensions
`analysis:*`	Music theory analysis
`mei:*`	MEI compatibility
`midi:*`	MIDI-specific data
`render:*`	Rendering hints
`edit:*`	Editorial metadata

Extensions in MRS-Ops

When creating events via MRS-Ops, custom properties can be included in the operation:

(create-event
  :tmp-id "e1"
  :measure #uuid "..."
  :instrument violin-1
  :voice v1
  :beat 0
  :pitch C4
  :duration q
  :x-source "manuscript-page-47"
  :x-confidence 0.85)

The orchestrator preserves custom properties when applying the operation to canonical state.

Overview

MRS-S Format

Agent Workflows

Model & Validation

Extension Mechanisms

Custom Properties

Namespace Extensions

Registered Namespaces

Extensions in MRS-Ops

​Custom Properties

​Namespace Extensions

​Registered Namespaces

​Extensions in MRS-Ops

Custom Properties

Namespace Extensions

Registered Namespaces

Extensions in MRS-Ops