MailgentAPI ReferenceMessages
Update Labels
PATCH /v0/messages/:messageId
Add or remove labels on a message.
Scope: mail:manage
PATCH /v0/messages/{messageId}Request
{
"addLabels": ["read", "processed"],
"removeLabels": ["unread"]
}| Field | Type | Description |
|---|---|---|
addLabels | string[] | Labels to add |
removeLabels | string[] | Labels to remove |
Both fields are optional but at least one should be provided.
Response 200
{
"messageId": "<abc123@gmail.com>",
"labels": ["received", "read", "processed"],
"createdAt": "2026-03-28T12:00:00.000Z"
}Common Patterns
# Mark as read
{"addLabels": ["read"], "removeLabels": ["unread"]}
# Flag as important
{"addLabels": ["important"]}
# Archive
{"addLabels": ["archived"]}
# Mark as processed by agent
{"addLabels": ["processed"], "removeLabels": ["unread"]}MCP
Tool: mail.update_labels