LangBot/docs/event-based-agents/adapters/slack.md

Slack EBA Adapter

Structure

Slack is migrated into src/langbot/pkg/platform/adapters/slack/ with the standard EBA adapter layout:

• adapter.py owns lifecycle, listener dispatch, unified webhook handling, outbound send/reply, and event caches.
• event_converter.py maps Slack im and app_mention channel events to message.received.
• message_converter.py maps common MessageChain components to Slack text fallback and maps inbound Slack text/image payloads back to EBA components.
• api_impl.py provides cache-backed common read APIs.
• platform_api.py declares safe Slack-specific API actions.
• manifest.yaml declares slack-eba.

The legacy src/langbot/pkg/platform/sources/slack.py adapter is kept unchanged.

Configuration

Field	Required	Notes
webhook_url	No	Generated by LangBot. Paste it into Slack Event Subscriptions.
bot_token	Yes	Slack bot token, usually xoxb-....
signing_secret	Yes	Slack app signing secret.

Events

Event	Notes
message.received	Emitted for private im messages and channel app_mention events. Channel messages are mapped to group chats.
platform.specific	Reserved for Slack event types that are not converted into common message events.

Common APIs

Required:

• send_message
• reply_message

Optional:

• get_message
• get_user_info
• get_friend_list
• get_group_info
• get_group_list
• get_group_member_list
• get_group_member_info
• call_platform_api

Cache-backed APIs are only available after the relevant inbound event has been observed.

Platform APIs

Action	Notes
get_mode	Returns webhook mode and configured bot account id.
auth_test	Calls Slack auth.test with the configured bot token.

Known Limits

• Slack file/image outbound is currently represented as text fallback because the existing Slack SDK wrapper only exposes chat_postMessage.
• Inbound channel coverage follows the legacy adapter behavior: only app_mention events are treated as group messages.
• Real live testing requires a public callback URL configured in Slack Event Subscriptions.

Verification

Local mocked unit coverage validates manifest parity, event conversion, legacy listener compatibility, cache-backed APIs, send/reply routing, and declared platform APIs.

Plugin E2E evidence was captured on June 2, 2026 against dev.rockchin.top with Slack private DM input and EBAEventProbe through the standalone runtime.

Evidence file: /home/wgc/LangBotxg/LangBotEbaTest/data/temp/slack_eba_plugin_probe.jsonl.

Observed:

• Real Slack private text produced MessageReceived with adapter_name=slack-eba, Source + Plain, private chat type, and filled bot_uuid.
• Safe common APIs passed: get_message, get_user_info, get_friend_list.
• Outbound component fallback sweep passed through send_message: plain/at/face, image, quote, file, and forward.
• Declared Slack platform APIs passed: get_mode, auth_test.

Still pending:

• Channel app_mention plugin E2E.
• Real inbound Slack file/image UI evidence.

Live probe scaffold: tests/e2e/live_slack_eba_probe.py.