missing-applyTo

What it catches#

Copilot instructions file has neither applyTo nor description.

A Copilot *.instructions.md file with neither applyTo nor description in its frontmatter, or with no frontmatter at all.

Why it matters#

VS Code uses such a file only when you attach it by hand.

# Testing conventions

- Use Vitest, not Jest.
- One `describe` per exported function.

---
applyTo: "**/*.test.ts"
description: Testing conventions for the Vitest suites
---

# Testing conventions

- Use Vitest, not Jest.
- One `describe` per exported function.

How to fix#

Add applyTo with a glob relative to the workspace root (** for every file) so the instructions attach when matching files are edited, or description so the agent can pick the file up when the task matches. Both is best.

Suppress or configure#

For one finding, put a comment on the line above it. The reason after -- is optional but worth writing:

<!-- asitis-disable-next-line missing-applyTo -- why this one is fine -->

For a whole file:

<!-- asitis-disable-file missing-applyTo -- why this file is an exception -->

For every file, turn it off or change its severity in .asitisrc.json:

{ "rules": { "missing-applyTo": "off" } }

A .asitisrc.json overrides entry limits a change to some paths, and a baseline (asitis lint --format json --write-baseline) accepts today's findings so only new ones fail the build.

Source#

VS Code docs: Custom instructions, read on 14 October 2026.