# EPUBCheck OPF-014: manifest property missing, how to fix it

Source: https://epubcc.com/epubcheck/opf-014/ (updated 2026-11-04)

EPUBCheck OPF-014 is an error message: “The property "…" should be declared in the OPF file.” A content document uses a feature that must be declared on its manifest item, and the declaration is missing. EPUB requires these properties so reading apps know in advance which documents need SVG, MathML, scripting or network access.

- Official message (EPUBCheck 5.4.0): The property "%1$s" should be declared in the OPF file.
- Default severity: Error

## Typical causes

- Inline SVG in an XHTML document whose manifest item lacks properties="svg".
- MathML without "mathml", or scripts (including forms or event attributes) without "scripted".
- Audio, video or fonts loaded from the web without "remote-resources" on the manifest item.

## How to fix it

1. Read the property name and the file in the message.
2. Add that property to the file's manifest item, for example <item id="c1" href="ch1.xhtml" media-type="application/xhtml+xml" properties="svg"/>.
3. Separate several properties with spaces, such as properties="svg mathml".
4. Run EPUBCheck again; if the feature was not intended, remove it from the document instead.

## When it's not this

If the property is declared but the document does not use the feature, that is OPF-015, the opposite case.

## Sources

- EPUB 3.3, §5.6.2.1 Resource properties: https://www.w3.org/TR/epub-33/#sec-item-resource-properties (read 2026-11-04)

Message text and severity: EPUBCheck (W3C, BSD-3-Clause). Explanation: EpubCC.