larksuite/cli · error

recipient address is empty

Error message

recipient address is empty

What it means

setRecipients validates every Address in the list being assigned to a to/cc/bcc field. If any entry has an Address value that is empty or whitespace-only, the entire patch op is rejected because a header entry without an address cannot be serialized. Note the operation is all-or-nothing: one bad entry blocks the whole set.

Source

Thrown at shortcuts/mail/draft/patch.go:166

}

func ensureHeaderEditable(name string, options PatchOptions) error {
	if protectedHeaders[strings.ToLower(strings.TrimSpace(name))] && !options.AllowProtectedHeaderEdits {
		return fmt.Errorf("header %q is protected; rerun with allow_protected_header_edits", name)
	}
	return nil
}

func setRecipients(snapshot *DraftSnapshot, field string, addrs []Address) error {
	field = strings.ToLower(strings.TrimSpace(field))
	if !isRecipientField(field) {
		return fmt.Errorf("recipient field must be one of to/cc/bcc")
	}
	normalized := make([]Address, 0, len(addrs))
	seen := map[string]bool{}
	for _, addr := range addrs {
		if strings.TrimSpace(addr.Address) == "" {
			return fmt.Errorf("recipient address is empty")
		}
		key := strings.ToLower(strings.TrimSpace(addr.Address))
		if seen[key] {
			continue
		}
		seen[key] = true
		normalized = append(normalized, Address{
			Name:    addr.Name,
			Address: strings.TrimSpace(addr.Address),
		})
	}
	_, headerName := recipientField(snapshot, field)
	setRecipientField(snapshot, headerName, normalized)
	return nil
}

func addRecipient(snapshot *DraftSnapshot, field string, addr Address) error {
	if strings.TrimSpace(addr.Address) == "" {

View on GitHub (pinned to 7fd6ef3c07)

Solutions

1. Filter out entries with empty/whitespace Address values before calling set_recipients
2. Parse display-name-style input so Address is extracted (e.g. 'Bob <bob@x.com>' -> bob@x.com) instead of storing only the name
3. If the whole field should be cleared, pass an empty list rather than a list containing a blank address

Example fix

// before
setRecipients(snap, "to", []Address{{Name: "Bob", Address: ""}})
// after
addrs := []Address{{Name: "Bob", Address: ""}}
var valid []Address
for _, a := range addrs {
    if strings.TrimSpace(a.Address) != "" {
        valid = append(valid, a)
    }
}
setRecipients(snap, "to", valid)

func validRecipients(addrs []Address) bool {
    for _, a := range addrs {
        if strings.TrimSpace(a.Address) == "" {
            return false
        }
    }
    return true
}

func hasAddress(a Address) bool { return strings.TrimSpace(a.Address) != "" }

When it happens

Trigger: Calling set_recipients (via applyOp) or buildDraftEditPatch with an Address whose Address field is "" or only spaces, e.g. parsing "Name <" or splitting an address list that ends with a separator.

Common situations: Building recipient lists from user input or CSV rows where a trailing comma or blank row yields an empty address; programmatic name-only entries (Name set, Address empty); template placeholders never filled in.

Understand the failure class

Background: "must not be empty", "cannot be empty" — required-field validation errors across open-source libraries — this error's family across 41 libraries.

Related errors

• recipient field must be one of to/cc/bcc
• draft main body is text/html and text/plain is only its summ
• unsupported body kind %q
• set_calendar: event_start must be a valid ISO 8601 timestamp
• set_calendar: event_end must be a valid ISO 8601 timestamp

AI-assisted analysis of larksuite/cli@7fd6ef3c07 (2026-09-04). Data as JSON: /api/errors/99b51aa37a3f5001. Report an issue: GitHub.