NPM `package.json` JSON schema: While IntelliSense works as expected, the popup message does not reflect the schema title.

[sangafabrice]

Does this issue occur when all extensions are disabled?: Yes/No

• VS Code Version: 1.106.2 (user setup)
• OS Version: Windows 10

Steps to Reproduce:

1. Download the package.json schema from SchemaStore into .vscode/package.schema.json at the workspace root:

   curl https://www.schemastore.org/package.json --output .vscode/package.schema.json

   The schema defines the title as:

   {
     "$schema": "http://json-schema.org/draft-07/schema#",
     "title": "JSON schema for NPM package.json files"
     ...
   }

2. Map the schema to package.json files in .vscode/settings.json:

   {
       "json.schemas": [
           {
               "fileMatch": [ "/package.json" ],
               "url": "./.vscode/package.schema.json"
           }
       ],
       "json.schemaDownload.enable": false
   }

3. Open a package.json file and hover over the opening curly bracket {.
   Instead of showing the schema title, the hover still displays the default message:

   XML Language server contributions to package.json
   

   

---

Additional Notes

• The issue is not limited to SchemaStore downloads. Even if the schema title is manually modified and json.schemaDownload.enable is set to true, the updated title does not appear in package.json files.
• This suggests the schema title is consistently overridden by the default message, regardless of configuration.

[aeschli]

In VS Code, the schema for a specific file (e.g. package.json) consists of a combination of all schema contributions that match that resource.
For package.json that's the main schema (from SchemaStore) and more from VS Code and several extensions. Each contribution adds additional validation e.g. for added properties.
XML is an example: https://github.com/redhat-developer/vscode-xml/blob/e066b621f8bbcde945c2e9d5444a65bad90031e8/schemas/package.schema.json#L3

Unfortunately they added a title which is now seen as tooltip. If there are multiple titles provided, we just pick one.
Schema additions should not provide a title.
I created redhat-developer/vscode-xml#1118