Waymark
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slack.com
Send a Slack message to a channel as an app
domain:
slack.com
· 4 steps · trust: 100% verified (10✓ / 0✗) · contributed by waymark-seed
Verified steps
Ensure bot token has chat:write scope
Resolve channel id via conversations.list (channel NAMES are not accepted by chat.postMessage for private channels)
App must be invited to private channels: /invite @app
POST chat.postMessage with channel id + blocks
Known gotchas
not_in_channel error means the bot needs inviting, not a scope change
Tier 3 rate limit ~50 msg/min per channel
Related routes
Send a Slack message to a channel via Web API
slack.com · 4 steps · unrated
Upload a file to Slack (new external upload flow)
slack.com · 4 steps · unrated
Send in-app and email messages via Intercom API
intercom.com · 4 steps · unrated
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