Returns the messages in a conversation newest first, both received and sent; page older messages with `starting_after` (fixed sort — render conversation order by reversing the page). By default every message that is not in the trash is returned, whichever folder the conversation is in; pass `label` to narrow the view instead — `trash` for trashed messages, or any custom label. Pass `include=extracted_text` to inline each message's extracted plain text. A thread whose retention period has ended returns `410 Gone`. Filter to received (`inbound`) or sent (`outbound`) messages. Possible values: `inbound`, `outbound` Filter to messages carrying this label. `trash` lists trashed messages; any other label — `archive`, `spam`, `blocked`, `unread`, or a custom label — lists its non-trashed carriers. When omitted, received messages in the inbox and all sent messages are returned. Set to `extracted_text` to inline each message's extracted plain text. Possible values: `extracted_text` 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. Message ID. Received messages carry a `rem_` ID, sent messages an `em_` ID — the same IDs used by the received-message and sent-message logs. Direction of the message — `inbound` for a received message, `outbound` for a sent one. Possible values: `inbound`, `outbound` Channel this message was carried on. Always `email`. Conversation this message belongs to. Sender address. Recipient addresses on the To line. Recipient addresses on the Cc line. Empty when the message had none. Address the message was actually delivered to, when it differs from the mailbox address (for example mail routed in from another address). Null for sent messages and for mail addressed directly to the mailbox. Message subject. Null when the message had no subject. Short plain-text preview of the message body. Plain-text content of the message with quoted history stripped — readable for the mailbox's full retention period, both directions. Always present when fetching a single message; on list endpoints it is included only when the request sets `include=extracted_text`. Null when no text could be extracted. Labels on this message. System labels carry its state: a received message holds exactly one placement label — `inbox` for accepted mail, `archive` when its conversation was filed away, `spam` (failed sender authentication), or `blocked` (rejected by the mailbox's receive policy or rules) — plus `unread` until it is read. `trash` marks a message in the trash, either direction. Custom labels share the same list; a message carries at most 20. Folded delivery status of a sent message: `accepted`, `sent` (provider handoff), `delivered` (all attempted recipients delivered), or `failed` (terminal failure). Null for received messages. Terminal per-recipient delivery outcomes of a sent message, folded in as they become known — part of the message's durable memory. Null for received messages and before any recipient reaches a terminal state. Per-recipient event detail lives on the sent-message log (`source`) for 30 days. Whether the sender of a received message was authenticated. `pass` means the sender's identity was verified; `fail` means it was checked and did not verify; `unknown` means no verdict could be determined and the sender should not be treated as verified. Null for sent messages. Part of the message's durable memory — readable for the mailbox's full retention period, so the verdict survives after the 30-day inbound log has expired. Possible values: `pass`, `fail`, `unknown`, `null` Whether SPF passed for the sender of a received message. Null for sent messages and when no verdict is available. Durable for the mailbox's retention period. Whether DKIM passed for the sender of a received message. Null for sent messages and when no verdict is available. Durable for the mailbox's retention period. Whether DMARC passed for the sender of a received message. Null for sent messages and when no verdict is available. Durable for the mailbox's retention period. When the message will be permanently deleted: the end of the mailbox's retention period, pulled nearer (at most 30 days out) while the message is in the trash. Restore a trashed message before then with `PATCH {"labels": {"remove": ["trash"]}}`. Number of attachments on the message. Attachment metadata (filename, content type, size). Remains readable for the mailbox's retention period even after the attachment bytes themselves have expired. Attachment ID, used to download the attachment bytes. Original filename, or null when the attachment had none. MIME content type, or null when it could not be determined. Attachment size in bytes. RFC 5322 References header entries used to thread the conversation. Contact linked to this message, or null when none is linked. Link to the message's entry in the received-message or sent-message log, which carries delivery analytics such as per-recipient events. Log entries expire 30 days after the message occurred. API path of the log entry for this message. When the log entry (and the message's original rendered source) expires. When the message was received or accepted for sending. 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`.