Error trying to create a product (using productSet) with metafields

Shopify Apps

Topic summary

A developer is encountering an error when attempting to create a product via Shopify’s productSet GraphQL Admin API mutation while including metafields.

Error Details:

  • Error message: “Owner subtype does not match the metafield definition’s constraints”
  • Occurs when passing a metafield with namespace “custom”, key “material”, and value ["Silikon"]

Attempted Solutions:

  • Tried multiple metafield types: single_line_text_field, list.single_line_text_field, and single_line_text
  • None of these type variations resolved the issue

Context:

  • The metafield definition exists and is visible in the Shopify admin (screenshots provided)
  • The error suggests a mismatch between the owner subtype being used and the metafield definition’s configured constraints
  • The developer has been unable to find documentation or similar cases online

Status: The issue remains unresolved with no responses yet. The core problem appears to be a configuration mismatch related to metafield owner constraints.

Summarized with AI on October 31. AI used: claude-sonnet-4-5-20250929.
1

I’m trying to create a product using the productSet GraphQL Admin API operation, and I provide this metafield:

[{ namespace: “custom”, key: “material”, value: “["Silikon"]”, type: “single_line_text_field” }]

on the ProductSetInput.metafields. I have also tried using the types “list.single_line_text_field” and “single_line_text”.

I get this error that I can’t find anything about on the internet:

[{“field”:[“input”,“metafields”,“0”],“message”:“Owner subtype does not match the metafield definition’s constraints.”}]

This is the metafield:

metafield.png
metafield.png727×614 13.4 KB

It is in this list:

metafield-in-list.png
metafield-in-list.png589×226 7.19 KB