GoogleContainerTools/skaffold · error

no tag provided for image [%s]

Error message

no tag provided for image [%s]

What it means

validateArtifactTags iterates over merged build artifacts and fails if any artifact has an empty Tag. Tags are produced by the tag strategy (envTemplate, dateTime, gitCommit, sha256, etc.); an empty tag means the builder could not derive an image tag, so the merged build output would be unusable downstream (deploy expects fully tagged images).

Source

Thrown at cmd/skaffold/app/cmd/util.go:102

				artifact.Tag = artifact.ImageName + ":" + opts.CustomTag
			} else {
				newTag, err := tag.SetImageTag(artifact.Tag, opts.CustomTag)
				if err != nil {
					return nil, err
				}
				artifact.Tag = newTag
			}
			result = append(result, artifact)
		}
		return result, nil
	}
	return artifacts, nil
}

func validateArtifactTags(artifacts []graph.Artifact) error {
	for _, artifact := range artifacts {
		if artifact.Tag == "" {
			return fmt.Errorf("no tag provided for image [%s]", artifact.ImageName)
		}
	}
	return nil
}

View on GitHub (pinned to a1189de023)

Solutions

1. Regenerate the build output with `skaffold build --file-output artifacts.json` instead of hand-editing it.
2. Check your tagger config in skaffold.yaml; ensure envTemplate references defined env vars so the tag is non-empty.
3. Inspect the artifacts JSON and ensure every entry has a non-empty `tag` field.

Example fix

// before (hand-edited artifacts.json)
[{"imageName":"gcr.io/proj/app","tag":""}]
// after
[{"imageName":"gcr.io/proj/app","tag":"gcr.io/proj/app:abc123"}]

for _, a := range artifacts {
    if a.Tag == "" {
        return fmt.Errorf("artifact %q has empty tag; rerun skaffold build", a.ImageName)
    }
}

if err := deployCmd.Run(); err != nil {
    if strings.Contains(err.Error(), "no tag provided for image") {
        // regenerate build output via `skaffold build --file-output`
    }
}

When it happens

Trigger: Calling mergeBuildArtifacts with build results whose `Tag` field is empty — typically when a custom builder/cache path returns artifacts without tags, or when merging artifacts loaded from a file (`--build-artifacts` / `--file-output`) that was hand-edited or produced by an older skaffold version.

Common situations: Piping `skaffold build --file-output` results into `skaffold deploy` after manual editing; custom build scripts emitting JSON without the `tag` field; tag template rendering to an empty string (e.g. missing env var in envTemplate tagger).

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• cannot add an empty image value
• executing build: %w
• validating upgraded config: %w
• executing build: %w
• failed to build: %w

AI-assisted analysis of GoogleContainerTools/skaffold@a1189de023 (2026-09-05). Data as JSON: /api/errors/3135718d99191934. Report an issue: GitHub.