lark-im

im (v1)

CRITICAL — MUST read ../lark-shared/SKILL.md with a Read tool before starting; it contains authentication and permission handling

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.
• Feed Shortcut: A chat pinned to the current user's feed sidebar, identified by feed_card_id (an oc_xxx open_chat_id for CHAT type).
• Feed Group: A tag that groups feed cards in the feed list, identified by feed_group_id (ofg_xxx). Members are feed cards, each identified by feed_id + feed_type. Two types: normal (members managed explicitly) and rule (members auto-derived from rules).

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

When fetching messages (+chat-messages-list, +threads-messages-list, +messages-mget, +messages-search), the CLI shows a display name for both user and bot senders:

• Server-provided name: the read APIs return sender_name (plus the full-i18n sender_i18n_names map) on each message sender; the CLI surfaces it as the sender's name for users and bots alike. No name lookup and no extra permission are needed — no contact scope and no application:bot.basic_info:read.
• Fallback to id: when the server does not provide a name, the sender is shown by its id and the command still exits 0. There is no contact-directory fallback.

The raw sender_name is not duplicated in output (its value is in name); the full sender_i18n_names map (all locales) is preserved for consumers that need a specific language, alongside an optional open_bot_id (ou_) for bot senders aligned with the message-receive event channel. System messages (msg_type: system) have no sender name — that is normal, not an error.

Default message enrichment (reactions / update_time)

The four message-pulling shortcuts (+messages-mget, +chat-messages-list, +messages-search, +threads-messages-list) automatically attach a reactions block and (for edited messages) update_time to each returned message — no separate im.reactions.batch_query call is needed. Pass --no-reactions to opt out. For the full contract (output shape, the im:message.reactions:read scope requirement, and the "missing field ≠ fetch failure" data rules), read references/lark-im-message-enrichment.md.

Opt-in resource auto-download (--download-resources)

+chat-messages-list, +messages-mget, and +threads-messages-list accept --download-resources (off by default — no resources block and no extra requests when omitted). When set, eligible message resources (image/file/audio/video/media + post-embedded; stickers excluded) are downloaded into ./lark-im-resources/ and each message gains a resources array of {message_id, key, type, local_path, size_bytes}. Downloads are deduped by (message_id, file_key), run with bounded concurrency, and isolate single-resource failures (error: true + stderr warning). Scope: requires im:message:readonly (already declared by the listing commands — no extra scope); works under both user and bot identity. For one-off downloads use +messages-resources-download. Full contract: references/lark-im-message-enrichment.md.

Card Messages (Interactive)

Before sending or replying with any interactive card (+messages-send / +messages-reply), you MUST read references/card/lark-im-card-create.md and follow its workflow. The card JSON passed to --msg-type interactive --content must be the output of that workflow — never hand-write or copy a card payload.

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.

interactive cards support callback events (card.action.trigger) — see references/lark-im-card-action-reply.md.

Audio Messages

--audio sends a voice message and supports only Opus audio files, for example .opus files or Ogg Opus (.ogg) files. For mp3, wav, or other non-Opus audio, either convert to .opus first and keep using --audio, or send the original file as an attachment with --file.

Sending Doc Content as a Message

When sending content fetched from a Lark doc as a message, fetch the doc with --doc-format im-markdown, then send it as a message using the --markdown format. The fetched content is already in markdown; in any content-forwarding scenario, keep the fetched original text and send it in the --markdown format. Note: if the doc contains a cite tag with type="user", keep it as-is and do not strip the tag.

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

Feed Shortcut

Feed shortcuts add chats to the current user's feed sidebar. They are distinct from flags:

• Flag = bookmark on a message/thread, scoped to the user's bookmark list.
• Feed shortcut = entry in the user's feed sidebar (currently only chats).

Key limits:

• Only CHAT-type (feed_card_id is oc_xxx) is exposed via OpenAPI; doc/app/subscription shortcuts exist internally but are not yet whitelisted.
• All three operations (create/remove/list) are user-identity only — they sign with user_access_token.
• Batch size is 10 per call for create/remove; list is a one-page wrapper with opaque page_token pagination.

Shortcuts (preferred)

Shortcuts are high-level wrappers for common operations (lark-cli im +<verb> [flags]). Use shortcuts when available.

Shortcut	Description
+chat-create	Create a group chat or topic chat; user/bot; --chat-mode group
+chat-list	List chats the current user/bot is a member of; defaults to groups; pass --types=p2p,group to include p2p single chats (user-only); user/bot; supports sorting, pagination, --exclude-muted (user-only)
+chat-members-list	List members of a chat; returns separate users[] / bots[] buckets; callable as user or bot; --member-types filters which kinds to return; --page-all pagination; surfaces truncations[] when the server caps a bucket
+chat-messages-list	List messages in a chat or P2P conversation; user/bot; accepts --chat-id or --user-id, resolves P2P chat_id, supports time range/sort/pagination
+chat-search	Search visible group chats by --query keyword and/or --member-ids; user/bot; e.g. look up chat_id by group name; supports type filters, sorting, pagination, and --exclude-muted (user identity only)
+chat-update	Update group chat name or description; user/bot; updates a chat's name or description
+messages-mget	Batch get messages by IDs; user/bot; fetches up to 50 om_ message IDs, formats sender names, expands thread replies
+messages-reply	Reply to a message (supports thread replies); user/bot; supports text/markdown/post/media replies, reply-in-thread, idempotency key
+messages-resources-download	Download images/files from a message; user/bot; supports automatic chunked download for large files (8MB chunks), auto-detects file extension from Content-Type
+messages-search	Search messages across chats (supports keyword, sender, time range filters) with user identity; user-only; filters by chat/sender/attachment/time, supports auto-pagination via --page-all / --page-limit, enriches results via batched mget and chats batch_query
+messages-send	Send a message to a chat or direct message; user/bot; sends to chat-id or user-id with text/markdown/post/media, supports idempotency key
+threads-messages-list	List messages in a thread; user/bot; accepts om_/omt_ input, resolves message IDs to thread_id, supports sort/pagination
+flag-create	Create a bookmark on a message; user-only; defaults to message-layer flag; use --flag-type feed for feed-layer flag (item_type auto-detected from chat mode)
+flag-cancel	Cancel (remove) a bookmark. When no --flag-type is given, best-effort double-cancel: removes message layer and (when chat_type is determinable) feed layer
+flag-list	List bookmarks; user-only; auto-enriches feed-type thread entries with message content; --page-all is capped by --page-limit (default 20, max 1000), and has_more=true means the result is incomplete
+feed-shortcut-create	Add chats to the user's feed shortcuts; user-only; oc_xxx chat IDs only; batch up to 10 per call; --head/--tail controls insertion order; partial failures return an ok:false ledger
+feed-shortcut-remove	Remove chats from the user's feed shortcuts; user-only; batch up to 10 per call; removing an absent shortcut is idempotent success; real per-item failures return an ok:false ledger
+feed-shortcut-list	List one page of the user's feed shortcuts; user-only; omit --page-token for the first page; default output enriches CHAT entries under detail; pass --no-detail to skip the extra lookup and im:chat:read scope
+feed-group-list	List the caller's feed groups (tags); user-only; supports --page-all auto-pagination
+feed-group-list-item	List feed cards in a feed group (tag); user-only; enriches each item with chat_name resolved from feed_id; supports --page-all auto-pagination
+feed-group-query-item	Look up specific feed cards in a feed group (tag) by ID; user-only; enriches each item with chat_name resolved from feed_id

API Resources

lark-cli schema im.<resource>.<method>   # Always check parameter structure before calling an API
lark-cli im <resource> <method> [flags] # Call the API

Important: When using raw APIs, always run schema first to see the --data / --params parameter structure; do not guess field formats.

chats

• create — Create a group. Identity: bot only (tenant_access_token).
• get — Get group info. Identity: supports user and bot; the caller must be in the target chat to get full details, and must belong to the same tenant for internal chats.
• link — Get group share link. Identity: supports user and bot; the caller must be in the target chat, must be an owner or admin when chat sharing is restricted to owners/admins, and must belong to the same tenant for internal chats.
• update — Update group info. Identity: supports user and bot.

chat.members

• create — Add users or bots to a group chat. Identity: supports user and bot; the caller must be in the target chat; for bot calls, added users must be within the app's availability; for internal chats the operator must belong to the same tenant; if only owners/admins can add members, the caller must be an owner/admin, or a chat-creator bot with im:chat:operate_as_owner.
• delete — Remove users or bots from a group chat. Identity: supports user and bot; only group owner, admin, or creator bot can remove others; max 50 users or 5 bots per request.

chat.user_setting

• batch_query — Batch query the current user's personal preferences in groups (e.g. is_muted mutes normal messages, is_mute_at_all mutes @all messages); up to 10 chats per request. Identity: user only (user_access_token); the caller must be in each target chat.
• batch_update — Batch update the current user's personal preferences in groups (e.g. is_muted mutes normal messages, is_mute_at_all mutes @all messages); up to 10 chats per request. Identity: user only (user_access_token); the caller must be in each target chat.

chat.nickname

• get — Get your own nickname in the chat (self-only). Identity: user only (user_access_token); returns an empty string when no nickname is set.
• update — Set or update your own nickname in the chat (self-only). Identity: user only (user_access_token); nickname must be a non-empty string (max 300 bytes). Use DELETE to clear it.
• delete — Clear your own nickname in the chat (self-only). Identity: user only (user_access_token).

chat.managers

• add_managers — Assign group managers. Identity: supports user and bot; only the group owner can add managers; max 10 managers per chat (20 for super-large chats), and at most 5 bots per request.
• delete_managers — Remove group managers. Identity: supports user and bot; only the group owner can remove managers; max 50 users or 5 bots per request.

chat.moderation

• get — Get group member speaking permissions. Identity: supports user and bot; the caller must be in the target chat and belong to the same tenant.
• update — Update group speaking permissions. Identity: supports user and bot; only the group owner (or creator bot with im:chat:operate_as_owner) can update; the caller must be in the chat.

messages

• delete — Recall a message. Identity: supports user and bot; for bot calls, the bot must be in the chat to revoke group messages; to revoke another user's group message, the bot must be the owner, an admin, or the creator; for user P2P recalls, the target user must be within the bot's availability.
• forward — Forward a message. Identity: supports user and bot.
• merge_forward — Merge and forward messages. Identity: bot only (tenant_access_token).
• read_users — Query message read status. Identity: bot only (tenant_access_token); the bot must be in the chat, and can only query read status for messages it sent within the last 7 days.
• urgent_app — Send in-app urgent notification. Identity: bot only (tenant_access_token); the bot must be the message sender and must be in the conversation that contains the message.
• urgent_phone — Send phone urgent notification. Identity: bot only (tenant_access_token); the bot must be the message sender and must be in the conversation that contains the message.
• urgent_sms — Send SMS urgent notification. Identity: bot only (tenant_access_token); the bot must be the message sender and must be in the conversation that contains the message.

reactions

• batch_query — Batch get message reactions. Identity: supports user and bot.Must-read
• create — Add a reaction to a message. Identity: supports user and bot; the caller must be in the conversation that contains the message.Must-read
• delete — Delete a reaction from a message. Identity: supports user and bot; the caller must be in the conversation that contains the message, and can only delete reactions added by itself.Must-read
• list — List reactions on a message. Identity: supports user and bot; the caller must be in the conversation that contains the message.Must-read

threads

• forward — Forward a thread. Identity: supports user and bot.

images

• create — Upload an image. Identity: bot only (tenant_access_token).

pins

• create — Pin a message. Identity: supports user and bot.
• delete — Unpin a message. Identity: supports user and bot.
• list — List pinned messages in a group. Identity: supports user and bot.

feed.groups

• batch_add_item — Batch add feed cards to a feed group. Identity: user only (user_access_token).Must-read
• batch_query — Batch query feed groups. Identity: user only (user_access_token).Must-read
• batch_remove_item — Batch remove feed cards from a feed group. Identity: user only (user_access_token).Must-read
• create — Create a feed group. Identity: user only (user_access_token).Must-read
• delete — Delete a feed group. Identity: user only (user_access_token).Must-read
• update — Update a feed group. Identity: user only (user_access_token).Must-read

Permission Table

Method	Required Scope
chats.create	im:chat:create
chats.get	im:chat:read
chats.link	im:chat:read
chats.update	im:chat:update
chat.members.create	im:chat.members:write_only
chat.members.delete	im:chat.members:write_only
chat.members.get	im:chat.members:read
+chat-members-list	im:chat.members:read
chat.user_setting.batch_query	im:chat.user_setting:read
chat.user_setting.batch_update	im:chat.user_setting:write
chat.managers.add_managers	im:chat.managers:write_only
chat.managers.delete_managers	im:chat.managers:write_only
chat.moderation.get	im:chat.moderation:read
chat.moderation.update	im:chat:moderation:write_only
messages.delete	im:message:recall
messages.forward	im:message
messages.merge_forward	im:message
messages.read_users	im:message:readonly
messages.urgent_app	im:message.urgent
messages.urgent_phone	im:message.urgent:phone
messages.urgent_sms	im:message.urgent:sms
reactions.batch_query	im:message.reactions:read
reactions.create	im:message.reactions:write_only
reactions.delete	im:message.reactions:write_only
reactions.list	im:message.reactions:read
threads.forward	im:message
images.create	im:resource
pins.create	im:message.pins:write_only
pins.delete	im:message.pins:write_only
pins.list	im:message.pins:read
feed.groups.batch_add_item	im:feed_group_v1:write
feed.groups.batch_query	im:feed_group_v1:read
feed.groups.batch_remove_item	im:feed_group_v1:write
feed.groups.create	im:feed_group_v1:write
feed.groups.delete	im:feed_group_v1:write
feed.groups.update	im:feed_group_v1:write