Feishu / Lark IM

Operate Feishu or Lark IM APIs via UXC + curated OpenAPI schema

Feishu / Lark IM Skill

Use this skill to run Feishu or Lark IM operations through uxc + OpenAPI.

Reuse the uxc skill for shared execution, auth, and error-handling guidance.

Prerequisites

• uxc is installed and available in PATH.
• Network access to https://open.feishu.cn/open-apis or https://open.larksuite.com/open-apis.
• Access to the curated OpenAPI schema URL:
  • https://raw.githubusercontent.com/holon-run/uxc/main/skills/feishu-openapi-skill/references/feishu-im.openapi.json
• A Feishu or Lark app with bot capability enabled.
• A Feishu or Lark app app_id + app_secret, or a current tenant_access_token if you are using the manual fallback path.

Scope

This skill covers an IM-focused request/response surface:

• chat lookup
• chat member lookup
• image and file upload for IM sends
• message send and reply
• selected message history reads
• basic user lookup through contact APIs

This skill does not cover:

• docs, bitable, approval, or non-IM product families
• the full Feishu or Lark Open Platform surface

Subscribe Status

Feishu and Lark expose event-delivery models beyond plain request/response APIs, including long-connection event delivery in the platform ecosystem.

Current uxc subscribe status:

• request/response IM operations are validated
• inbound message intake is validated through the built-in feishu-long-connection transport
• live validation confirmed real im.message.receive_v1 events delivered into the subscribe sink for a p2p bot chat

Important runtime notes:

• feishu-long-connection is a provider-aware transport inside uxc subscribe; it is not a plain raw WebSocket stream
• the runtime opens a temporary WebSocket URL from /callback/ws/endpoint
• frames are protobuf binary messages, not text JSON
• the runtime sends required event acknowledgements and ping control frames automatically

Endpoint Choice

This schema works against either Feishu or Lark Open Platform base URLs:

• China / Feishu default: https://open.feishu.cn/open-apis
• International / Lark alternative: https://open.larksuite.com/open-apis

The fixed link example below uses Feishu. For Lark, use the same schema URL against the Lark base host.

Authentication

Feishu and Lark service-side APIs use Authorization: Bearer <tenant_access_token> for these operations.

Preferred setup is to store app_id + app_secret as credential fields and let uxc auth bootstrap fetch and refresh the short-lived tenant token automatically.

Feishu bootstrap-managed setup:

bash

uxc auth credential set feishu-tenant \
  --auth-type bearer \
  --field app_id=env:FEISHU_APP_ID \
  --field app_secret=env:FEISHU_APP_SECRET

uxc auth bootstrap set feishu-tenant \
  --token-endpoint https://open.feishu.cn/open-apis/auth/v3/tenant_access_token/internal \
  --header 'Content-Type=application/json; charset=utf-8' \
  --request-json '{"app_id":"{{field:app_id}}","app_secret":"{{field:app_secret}}"}' \
  --access-token-pointer /tenant_access_token \
  --expires-in-pointer /expire \
  --success-code-pointer /code \
  --success-code-value 0

uxc auth binding add \
  --id feishu-tenant \
  --host open.feishu.cn \
  --path-prefix /open-apis \
  --scheme https \
  --credential feishu-tenant \
  --priority 100

For Lark, use the same bootstrap shape against the Lark host and bind the credential to open.larksuite.com.

To use long-connection subscribe, the credential still needs app_id and app_secret fields because the transport opens its own temporary event URL outside the normal bearer-token request path.

Manual fallback if you already have a tenant token:

bash

curl -sS https://open.feishu.cn/open-apis/auth/v3/tenant_access_token/internal \
  -H 'Content-Type: application/json; charset=utf-8' \
  -d '{"app_id":"cli_xxx","app_secret":"xxxx"}'

Lark uses the same path shape on the Lark host:

bash

curl -sS https://open.larksuite.com/open-apis/auth/v3/tenant_access_token/internal \
  -H 'Content-Type: application/json; charset=utf-8' \
  -d '{"app_id":"cli_xxx","app_secret":"xxxx"}'

Configure one bearer credential and bind it to the Feishu API host:

bash

uxc auth credential set feishu-tenant \
  --auth-type bearer \
  --secret-env FEISHU_TENANT_ACCESS_TOKEN

uxc auth binding add \
  --id feishu-tenant \
  --host open.feishu.cn \
  --path-prefix /open-apis \
  --scheme https \
  --credential feishu-tenant \
  --priority 100

For Lark, create the same binding against open.larksuite.com:

bash

uxc auth binding add \
  --id lark-tenant \
  --host open.larksuite.com \
  --path-prefix /open-apis \
  --scheme https \
  --credential feishu-tenant \
  --priority 100

Inspect or pre-warm bootstrap state when auth looks wrong:

bash

uxc auth bootstrap info feishu-tenant
uxc auth bootstrap refresh feishu-tenant

Validate the active binding when auth looks wrong:

bash

uxc auth binding match https://open.feishu.cn/open-apis

Core Workflow

1. Use the fixed link command by default:

   • command -v feishu-openapi-cli
   • If missing, create it: uxc link feishu-openapi-cli https://open.feishu.cn/open-apis --schema-url https://raw.githubusercontent.com/holon-run/uxc/main/skills/feishu-openapi-skill/references/feishu-im.openapi.json
   • feishu-openapi-cli -h

2. Inspect operation schema first:

   • feishu-openapi-cli get:/im/v1/chats -h
   • feishu-openapi-cli post:/im/v1/images -h
   • feishu-openapi-cli post:/im/v1/files -h
   • feishu-openapi-cli post:/im/v1/messages -h
   • feishu-openapi-cli get:/im/v1/messages -h

3. Prefer read/setup validation before writes:

   • feishu-openapi-cli get:/im/v1/chats page_size=20
   • feishu-openapi-cli get:/im/v1/chats/{chat_id} chat_id=oc_xxx
   • feishu-openapi-cli get:/contact/v3/users/{user_id} user_id=ou_xxx user_id_type=open_id

4. Execute with key/value or positional JSON:

   • key/value: feishu-openapi-cli get:/im/v1/messages container_id_type=chat container_id=oc_xxx page_size=20
   • multipart upload: feishu-openapi-cli post:/im/v1/images image_type=message image=/tmp/example.png
   • positional JSON: feishu-openapi-cli post:/im/v1/messages receive_id_type=chat_id '{"receive_id":"oc_xxx","msg_type":"text","content":"{\"text\":\"Hello from UXC\"}"}'

5. For inbound message intake, use uxc subscribe directly:

   • uxc subscribe start https://open.feishu.cn/open-apis --transport feishu-long-connection --auth feishu-tenant --sink file:$HOME/.uxc/subscriptions/feishu.ndjson
   • send a bot-visible message, then inspect the sink for header.event_type = "im.message.receive_v1"

Operation Groups

Chat Reads

• get:/im/v1/chats
• get:/im/v1/chats/{chat_id}
• get:/im/v1/chats/{chat_id}/members

Message Reads / Writes

• get:/im/v1/messages
• get:/im/v1/messages/{message_id}
• post:/im/v1/messages
• post:/im/v1/messages/{message_id}/reply

Uploads

• post:/im/v1/images
• post:/im/v1/files

User Lookup

• get:/contact/v3/users/{user_id}
• post:/contact/v3/users/batch_get_id

Guardrails

• Keep automation on the JSON output envelope; do not use --text.
• Parse stable fields first: ok, kind, protocol, data, error.
• Prefer uxc auth bootstrap over manual token management. Manual tenant_access_token setup is still supported as a fallback.
• feishu-long-connection requires the app credential fields app_id and app_secret; a plain bearer-only credential is not enough for event intake.
• post:/im/v1/images and post:/im/v1/files use multipart/form-data. File fields must be local path strings; help output marks them as multipart file fields.
• post:/im/v1/messages requires the receive_id_type query parameter and the body content field is a JSON-encoded string, not a nested JSON object.
• Upload first, then send by returned key:
  • image sends use msg_type=image with content='{\"image_key\":\"img_xxx\"}'
  • file sends use msg_type=file with content='{\"file_key\":\"file_xxx\"}'
• post:/im/v1/messages/{message_id}/reply is for explicit replies to an existing message. Treat it as a high-risk write.
• History reads only return chats and messages visible to the bot/app configuration. Auth success does not imply access to every chat.
• Long-connection message intake is validated for Feishu bot chats; webhook-style callbacks and non-IM products are still out of scope.
• feishu-openapi-cli <operation> ... is equivalent to uxc https://open.feishu.cn/open-apis --schema-url <feishu_openapi_schema> <operation> ....

References

• Usage patterns: references/usage-patterns.md
• Curated OpenAPI schema: references/feishu-im.openapi.json
• Feishu Open Platform docs: https://open.feishu.cn/document/
• Lark Open Platform docs: https://open.larksuite.com/document/