larksuite-cli/skill-template/domains/im.md

Core Concepts

• Message: A single message in a chat, identified by message_id (om_xxx). Supports types: text, post, image, file, audio, video, sticker, interactive (card), share_chat, share_user, merge_forward, etc.
• Chat: A group chat or P2P conversation, identified by chat_id (oc_xxx).
• Thread: A reply thread under a message, identified by thread_id (om_xxx or omt_xxx).
• Reaction: An emoji reaction on a message.
• Flag: A bookmark on a message or thread.

Resource Relationships

Chat (oc_xxx)
├── Message (om_xxx)
│   ├── Thread (reply thread)
│   ├── Reaction (emoji)
│   └── Resource (image / file / video / audio)
└── Member (user / bot)

Important Notes

Identity and Token Mapping

• --as user means user identity and uses user_access_token. Calls run as the authorized end user, so permissions depend on both the app scopes and that user's own access to the target chat/message/resource.
• --as bot means bot identity and uses tenant_access_token. Calls run as the app bot, so behavior depends on the bot's membership, app visibility, availability range, and bot-specific scopes.
• If an IM API says it supports both user and bot, the token type changes who the operator is. The same API can succeed with one identity and fail with the other because owner/admin status, chat membership, tenant boundary, or app availability are checked against the current caller.

Sender Name Resolution with Bot Identity

When using bot identity (--as bot) to fetch messages (e.g. +chat-messages-list, +threads-messages-list, +messages-mget), sender names may not be resolved (shown as open_id instead of display name). This happens when the bot cannot access the user's contact info.

Root cause: The bot's app visibility settings do not include the message sender, so the contact API returns no name.

Solution: Check the app's visibility settings in the Lark Developer Console — ensure the app's visible range covers the users whose names need to be resolved. Alternatively, use --as user to fetch messages with user identity, which typically has broader contact access.

Card Messages (Interactive)

Card messages (interactive type) are not yet supported for compact conversion in event subscriptions. The raw event data will be returned instead, with a hint printed to stderr.

Flag Types

Flags support two layers:

• Message-layer flag: (ItemTypeDefault, FlagTypeMessage) — regular message bookmark
• Feed-layer flag: (ItemTypeThread/ItemTypeMsgThread, FlagTypeFeed) — thread as feed-layer bookmark

Item types for feed-layer flags:

• ItemTypeThread (4) = thread in a topic-style chat
• ItemTypeMsgThread (11) = thread in a regular chat