Draft changelog: weekly roundup for Aug 28

[mintlify]

Summary

Adds an Aug 28, 2026 changelog entry covering product changes shipped since the last entry (Aug 13).

Changes

• New features: Chat API bot endpoints (/2/bots), broadcast.start/broadcast.end X Activity API events, filter.qualifiers for Activity subscriptions, GET /2/usage/credits, and the delete Chat messages endpoint.
• Updates: Pay-Per-Use monthly Post cap raised from 2M to 3M, and the new is_subscriber field on broadcast.chat payloads.
• Excludes docs-only fixes (Trends tweet_count correction, blank Community Notes page, nav fixes, customer directory update).

Context

Based on PRs #313, #323, #324, #329, #337, #340, and #342 merged since the last changelog entry.

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Project	Status	Preview	Updated (UTC)
x-corp	🟢 Ready	View Preview	Aug 28, 2026, 11:10 PM

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