googleapis/mcp-toolbox · error

invalid : must match

Error message

invalid %s %q: must match %s

What it means

ValidateGCEResourceName checks a VM name or zone name against the GCE resource-name rule ^[a-z]([-a-z0-9]{0,61}[a-z0-9])?$: lowercase letters, digits, and hyphens; must start with a letter, must not end with a hyphen, max 63 chars. The failing value is echoed in the message along with the kind ('vm', 'zone', etc.) supplied by the caller.

Solutions

1. Convert the name to lowercase and replace underscores with hyphens
2. Ensure it starts with a letter and ends with a letter or digit, and is at most 63 characters
3. Verify the actual resource name with `gcloud compute instances list` or `gcloud compute zones list`

Example fix

// before
ValidateGCEResourceName("My_VM_01", "vm")
// after
ValidateGCEResourceName("my-vm-01", "vm")

var gceResourceRe = regexp.MustCompile(`^[a-z]([-a-z0-9]{0,61}[a-z0-9])?$`)
if err := cloudsqlconnect.ValidateGCEResourceName(vmName, "vm"); err != nil {
    return err
}
if err := cloudsqlconnect.ValidateGCEResourceName(zone, "zone"); err != nil {
    return err
}

func isValidGCEResource(name string) bool {
    return regexp.MustCompile(`^[a-z]([-a-z0-9]{0,61}[a-z0-9])?$`).MatchString(name)
}

if err := cloudsqlconnect.ValidateGCEResourceName(name, kind); err != nil {
    return fmt.Errorf("%w (GCE names: lowercase letters/digits/hyphens, start with a letter, max 63 chars)", err)
}

When it happens

Trigger: Calling FindVM-related tool flows (via Invoke) with a vm_name or vm_zone containing uppercase letters, underscores, spaces, a leading digit, or a trailing hyphen.

Common situations: VM names copied from cloud consoles of other providers; CamelCase names like 'MyVM'; zone typed as 'us_central1_a'; accidental trailing whitespace or hyphen from copy-paste.

Related errors

• failed to build token-scoped Compute Engine client
• failed to search for VM
• invalid Cloud SQL instance ID
• invalid connection name
• invalid project ID : must match

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/0aa4b08f9ee22a36. Report an issue: GitHub.

Appendix: source

Thrown at internal/util/cloudsqlconnect/inputvalidate.go:64

	}
	if !projectIDRe.MatchString(project) {
		return "", "", "", fmt.Errorf("invalid project ID %q: must match %s", project, projectIDRe)
	}
	if !gcpRegionRe.MatchString(region) {
		return "", "", "", fmt.Errorf("invalid region %q: must match %s", region, gcpRegionRe)
	}
	if !cloudSQLInstanceRe.MatchString(instance) {
		return "", "", "", fmt.Errorf("invalid Cloud SQL instance ID %q: must match %s", instance, cloudSQLInstanceRe)
	}
	return project, region, instance, nil
}

// ValidateGCEResourceName checks a VM name or zone name against the standard
// GCE resource-name rule (lowercase, digits, hyphen; must start with a letter
// and not end with a hyphen, max 63 chars).
func ValidateGCEResourceName(name, kind string) error {
	if !gceResourceRe.MatchString(name) {
		return fmt.Errorf("invalid %s %q: must match %s", kind, name, gceResourceRe)
	}
	return nil
}

// ValidateDatabaseName accepts the conservative subset of database identifier
// characters that's safe in DSNs and code-snippet templates across Postgres,
// MySQL and SQL Server. It deliberately rejects quotes, semicolons, and
// whitespace even when the engine itself would accept them.
func ValidateDatabaseName(name string) error {
	if !databaseNameRe.MatchString(name) {
		return fmt.Errorf("invalid database_name %q: must match %s", name, databaseNameRe)
	}
	return nil
}

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