Returns the SMTP send-option configs stored for API keys in this workspace, as a cursor page. Only keys with an explicitly stored config are included — a key with no config still accepts SMTP submissions, using your organization's default pool, the transactional category, and tracking on. Field to sort by. Possible values: `created_at` Sort direction. Defaults to `desc` (newest/largest first). Possible values: `asc`, `desc` Maximum number of items to return per page. Cursor from the `next_cursor` field of a previous list response. Returns items immediately after the cursor position in the current sort order. Cursor from the `prev_cursor` field of a previous list response. Returns items immediately before the cursor position in the current sort order. When true, the response includes a `total` field with the total number of items matching the request's filters across all pages. Page of stored SMTP configs, newest first by default. ID of the API key this config applies to, the same key your SMTP client authenticates with. One config exists per key. ID of the IP pool that SMTP sends with this key use, or `ipp_shared` for the shared pool. `null` when this key uses your organization's default pool. Content classification applied to messages submitted over SMTP with this key. Controls suppression policy: `marketing` blocks on all suppression reasons; `transactional` allows delivery through complaint and unsubscribe suppressions. Possible values: `marketing`, `transactional` Structured `{name, value}` labels applied to every message submitted over SMTP with this key — the same tags used by the email sending API. See EmailMessageSendRequest for how tags are used for filtering and analytics. Tag name. ASCII letters, digits, underscore, and hyphen only. Case-sensitive. Maximum 32 characters. Tag value. ASCII letters, digits, underscore, and hyphen only. Case-sensitive. Maximum 64 characters. Whether open events are tracked for messages submitted over SMTP with this key. Whether click events are tracked for messages submitted over SMTP with this key. Cursor for the next page. Pass back as `starting_after` to advance forward. Null when no next page exists. Cursor for the previous page. Pass back as `ending_before` to step backward. Null when no previous page exists. Refresh anchor. Pass back as `ending_before` later to fetch items that have appeared since this response. Non-null whenever `data` is non-empty; null only on an empty page. Distinct from `prev_cursor`. Total number of items matching the request's filters across all pages. Present only when `include_total=true` was passed; otherwise null.