The artifact custom_metadata feature was added in v1.19.0 (commit 2b0f9532) to support context offloading patterns, but the web server endpoints were not updated to expose this functionality.

Currently, when calling the web API, I can only:

• Get artifact content: GET /artifacts/{name} or GET /artifacts/{name}/versions/{id}
• List version numbers: GET /artifacts/{name}/versions returns list[int]
• List artifact names: GET /artifacts returns list[str]

None of these endpoints return the ArtifactVersion object with custom_metadata, which is essential for the context offloading pattern demonstrated in the context_offloading_with_artifact sample. This means web/HTTP clients cannot implement the same efficient context management that Python-based tools can use.

I would like web API endpoints that expose the artifact metadata functionality already available in the backend services.

I would also like info included artifactDelta as well for the streaming use cases.