A template must be supplied using '-template' when using go-

Error message

A template must be supplied using '-template' when using go-template formatting

What it means

VarGetCommand.validateOutputFlag requires -template when -output=go-template, because go-template rendering has nothing to render without one. This error is returned before any server request is made.

Source

Thrown at command/var_get.go:210

		},
		OpenURL: openURL,
	})
	if hint != "" {
		c.Ui.Warn(hint)
	}
	return 0
}

func (c *VarGetCommand) validateOutputFlag() error {
	if c.outFmt != "go-template" && c.tmpl != "" {
		return errors.New(errUnexpectedTemplate)
	}
	switch c.outFmt {
	case "hcl", "json", "none", "table":
		return nil
	case "go-template": //noop - needs more validation
		if c.tmpl == "" {
			return errors.New(errMissingTemplate)
		}
		return nil
	default:
		return errors.New(errInvalidOutFormat)
	}
}

func (c *VarGetCommand) GetConcurrentUI() cli.ConcurrentUi {
	return cli.ConcurrentUi{Ui: c.Ui}
}

View on GitHub (pinned to 482b49bf1a)

Solutions

Add a -template flag with a valid Go template, e.g. -template='{{ .Data.data }}'
Or switch -output to a format that needs no template (table, json, hcl, none)

Example fix

// before
vault kv get -output=go-template secret/foo
// after
vault kv get -output=go-template -template='{{ .Data.data.foo }}' secret/foo

Defensive patterns

Strategy: validation

Validate before calling

if outFmt == "go-template" && tmpl == "" {
	return errors.New("-output=go-template requires -template")
}

Try / catch

if err := cmd.validateOutputFlag(); err != nil {
	if strings.Contains(err.Error(), "template must be supplied") {
		// prompt user for -template or fall back to table output
	}
	return err
}

Prevention

When setting -output=go-template, always pair it with -template in the same command/profile
Default to table output in scripts to avoid template requirements
Keep go-template invocations in wrapper functions that enforce the template argument

When it happens

Trigger: Running `vault kv get -output=go-template <path>` without supplying -template (c.outFmt == "go-template" and c.tmpl == "").

Common situations: Setting the output format in config or a script but forgetting the template argument; aliasing `vault kv get -o go-template` assuming a default template exists.

Understand the failure class

Background: "--flag is required" and "must specify" CLI errors: how missing-required-flag validation works and how to fix it — this error's family across 20 libraries.

Related errors

AI-assisted analysis of hashicorp/nomad@482b49bf1a (2026-09-04). Data as JSON: /api/errors/08474b36ceda156b. Report an issue: GitHub.