Slack · infra · fg-0364

Slack events go missing in production while a developer runs the same app locally in Socket Mode

Some events reach the laptop and never reach the deployed app

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

Socket Mode allows up to 10 connections per app and Slack sends each payload to any one of them. A local process using the same app token takes a share of production traffic, and every connection is recycled every few hours.

Fix

Use a separate Slack app for development, handle reconnects on refresh_requested, and remember Socket Mode apps cannot be listed in the Marketplace.

Apply

SLACK_APP_TOKEN for local dev must belong to a separate development app, never the production app

Affects: Slack apps using Socket Mode, as of 2026-10

Sources

https://docs.slack.dev/apis/events-api/using-socket-mode

Have your agent know this before it fails

claude mcp add --transport http footgun https://getfootgun.com/api/mcp