diff --git a/Capabilities.md b/Capabilities.md
new file mode 100644
index 0000000..79f18c7
--- /dev/null
+++ b/Capabilities.md
@@ -0,0 +1,83 @@
+<!-- Generated from README.md by tools/build_wiki.py. Edit the source, not this page. -->
+
+> This page is generated from [`README.md`](https://git.tirsystem.com/TirSystem/github-action/src/branch/main/README.md). Changes made here are overwritten the next time the wiki is published.
+
+English | [Dansk](Capabilities.da) | [Bahasa Melayu](Capabilities.ms)
+
+## Capabilities
+
+Only the first row is implemented. The rest is planned and tracked in the [Project Plan](https://git.tirsystem.com/TirSystem/github-action/src/branch/main/docs/project-plan.md), which also describes each use case.
+
+| Capability | Status |
+| --- | --- |
+| Synchronize repository metadata (Gitea to GitHub mirror) | Implemented in `.gitea/scoped_workflows/`, with offline tests and a validation workflow |
+| Configure and validate workflow credentials | Implemented for the sync workflow: preflight checks both tokens before any change ([guide](Credentials)) |
+| Onboard a repository, manage runners, diagnose failures | Guides written ([onboarding](Onboarding), [troubleshooting](Troubleshooting)); scoped delivery to other repositories not yet verified; brief use cases open (MIL-002) |
+| Shared quality checks | Planned (MIL-003) |
+| Versioned release and publishing | Planned (MIL-004) |
+
+### Sync GitHub metadata
+
+Syncs the Gitea repository description and topics to the GitHub push mirror.
+
+#### Cron
+
+Daily at 03:17 UTC (`17 3 * * *`), plus every push to `main` and manual `workflow_dispatch`.
+
+#### Workflow
+
+```plantuml
+@startuml
+title Sync Gitea repository description and topics to GitHub
+
+autonumber
+
+actor "Push to main,\nmanual trigger, or schedule" as Trigger
+participant "Gitea Actions\nsync-github-metadata" as Workflow
+participant "Gitea REST API" as Gitea
+participant "GitHub REST API" as GitHub
+
+Trigger -> Workflow: Start workflow
+activate Workflow
+
+Workflow -> Workflow: Read and validate secrets
+note right
+TOKEN_FOR_GITEA
+CREDENTIALS_FOR_GITHUB
+end note
+
+alt secret validation failed
+  Workflow --> Trigger: workflow failed
+end
+
+
+Workflow -> Gitea: GET /repos/{owner}/{repo}
+Gitea --> Workflow: Description and topics
+
+Workflow -> Gitea: GET /repos/{owner}/{repo}/push_mirrors
+Gitea --> Workflow: Push mirror response
+
+alt mirrors is not a list
+    Workflow --> Trigger: Log a warning and succeed\n(GitHub metadata not synced)
+else mirrors is a list with no GitHub mirror
+    Workflow --> Trigger: Log that there is nothing to sync and succeed
+else mirrors is a list
+    Workflow -> Workflow: Find GitHub owner and repo from remote_address
+
+    Workflow -> GitHub: PATCH /repos/{owner}/{repo}\n{description}
+    GitHub --> Workflow: Repository updated
+
+    Workflow -> GitHub: PUT /repos/{owner}/{repo}/topics\n{names}
+    GitHub --> Workflow: Topics updated
+
+    Workflow --> Trigger: Sync completed
+else Gitea API denies access
+    Gitea --> Workflow: HTTP 403 Forbidden
+    Workflow --> Trigger: Workflow fails
+else GitHub API denies access
+    GitHub --> Workflow: HTTP error
+    Workflow --> Trigger: Workflow fails
+end
+deactivate Workflow
+@enduml
+```