Mastra Ships Durable Agent Sessions for Slack, Discord Threads

Mastra's 1.54.0 release turns every Slack, Discord, and Telegram thread into a durable agent session, per the July 30 GitHub release notes. AgentController adds chat-channel adapters that map each thread to one session, so state doesn't reset every time someone opens a new message.

For teams running chat-based AI assistants, that's one less thing to build by hand. The release adds native streaming and typing indicators. Tool-approval cards resolve through the session's own approval gate, and the controller owns the webhook routes.

The upgrade isn't free. Channel handlers take a fourth ChannelHandlerContext argument as of this release. That's a breaking change, and anyone with a custom handler has to touch that code before moving to 1.54.0.

Mastra also shipped MongoDB support in the same release, with bring-your-own-collection indexing and hybrid vector plus full-text retrieval. Exact metadata filtering on memory.recall works the same way across Postgres, MySQL, MongoDB, Redis, and ClickHouse.