Currently, Jira Cloud only supports a single site-wide announcement banner, accessible via GET/PUT /rest/api/3/announcementBanner, which requires the Administer Jira global permission. There is no native concept of a project-scoped announcement banner, and therefore no API to read or write one at the project level.
Use case: Forge app developers and integrators need the ability to define and read announcement/banner content scoped to a specific Jira project — for example, to surface project-specific notices, warnings, or status messages to users working within that project context.

Requested feature: A project-level announcement banner concept in Jira Cloud, manageable by project administrators. A corresponding REST API endpoint (e.g. GET/PUT /rest/api/3/project/{projectIdOrKey}/announcementBanner) to read and write project-scoped banner content. Forge API support so that Forge apps can read and render this content within the relevant project context.
Current workaround: Developers must implement a fully custom solution using Forge Storage keyed by project ID and render it via a UI Kit panel or Custom UI module. While functional, this does not leverage any native Jira platform capability and adds unnecessary complexity.