modelcontextprotocol / modelcontextprotocol/ext-apps
Properly clarify content model visibility - content vs structuredContent vs _meta
@liady is already working on this.
Since Jan 27, 2026.
- Dominant language
- TypeScript
- Stars
- 2.9k
- Forks
- 387
- Avg merge
- 3h 21m
- Merged PRs (30d)
- 6
Description
There were questions from the community about the proper field to use for passing data to the UI without the passing through the model.
The spec mentions (in a somewhat hard-to-find location) that content is passed to the model, and that both structuredContent and _meta are not added to the context. This needs further clarification.
In addition - it's not clear whether content needs to be shown in addition to the UI.
As a comparison - Apps SDK spec clearly specifies that content and structuredContent are being passed to the model, while _meta isn't.
We should probably make it clearer in the spec.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Assessment
This issue has not been assessed yet.