regctl tag ls: List Repository Tags
regctl tag ls prints all tags in a repository by querying the registry, no Docker daemon required.
regctl tag ls is the regclient equivalent of crane ls: it lists the tags of a repository so you can pick, promote, or clean them up.
What it does
regctl tag ls queries the registry tag listing endpoint for a repository and prints each tag. It respects the login and TLS settings you configure with regctl registry.
Common usage
# list tags
regctl tag ls ghcr.io/acme/app
# newest semver tag
regctl tag ls ghcr.io/acme/app | grep -E '^[0-9]' | sort -V | tail -1
# delete a specific tag
regctl tag rm ghcr.io/acme/app:pr-123Options
| Flag | What it does |
|---|---|
| REPO | Repository to list (positional) |
| --limit N | Limit the number of tags returned |
| --format <tmpl> | Go-template output (e.g. raw JSON) |
In CI
Pair regctl tag ls with regctl tag rm for daemonless tag cleanup, or with regctl image copy to promote a chosen tag. Configure the registry once per job with regctl registry login.
Common errors in CI
"401 Unauthorized" means run regctl registry login <host>. "repository not found" means the path is wrong or empty. "x509: certificate signed by unknown authority" on an internal registry needs a mounted CA or regctl registry set --tls insecure <host>.