---
title: "MGS7004: unknown marker family"
description: Fires when a source line carries a magus:<family> marker whose family magus does not know. The knowledge graph build fails naming the file, the line and the families it accepts.
tags: [MGS7004, knowledge graph, markers, graph build]
---

# MGS7004: unknown marker family

A marker is a declaration a person writes in source: `magus:<family>` followed
by its arguments, in whatever comment syntax the file uses. The knowledge graph
records each one as a `marker` node with `declared` confidence. The families
are `diagram` (a source file pointing at a figure), `calls` (a declared call to
another package), `skills` (the managed AGENTS.md block) and `observed` (a
generated figure block).

This code fires when `magus graph build` meets a family outside that list.

## Why

A marker nothing reads is a declaration nothing honors. Skipping it would let a
typo such as `magus:cals` pass as a declared edge that the graph never holds.

## Resolution

The message names the file, the line and the known families.

- **A typo.** Correct the family name.
- **Not a marker.** Text that happens to contain `magus:` followed by a word,
  such as a URL scheme in prose, needs rewording so the token does not start a
  marker.