---
url: >-
  https://adk.nht.io/api/@nhtio/adk/batteries/artifacts/variables/E_YAML_PEER_MISSING.md
description: Thrown when the js-yaml peer dependency is missing or fails to load.
---

# Variable: E\_YAML\_PEER\_MISSING

```ts
const E_YAML_PEER_MISSING: CreatedException<[string]>;
```

Defined in: [src/batteries/artifacts/yaml/exceptions.ts:26](https://github.com/NHTIO/ADK/blob/v1.20260907.0/src/src/batteries/artifacts/yaml/exceptions.ts#L26)

Thrown when the js-yaml peer dependency is missing or fails to load.

## Remarks

This occurs when the battery's consumer has not installed the optional js-yaml peer
dependency. The message template includes the package name, a description of its purpose,
the underlying error, and the exact install command, so the consumer sees a complete,
actionable message regardless of call site.