---
title: "MGS7006: layer not declared"
description: Fires when magus\layer or a dirs() layer filter names a layer that no magus.project "layers" key declares. The call raises rather than return an empty set.
tags: [MGS7006, knowledge graph, layers, magus\layer, figures, buzz]
---

# MGS7006: layer not declared

`magus\layer(name)` returns every directory a project's `layers` key assigns
to that name, and `magus\dirs(glob, opts: {layer})` filters by it.

This code fires when no project declares the layer.

## Why

An empty layer would let a figure draw a group that claims nothing, so every
package it meant to cover would go uncovered without a word.

## Resolution

- **A typo.** Correct the layer name.
- **A missing declaration.** Add the directories to a project's `layers` key,
  for example `"layers": {"internal/handler/*": "handler"}`.