Proactive Agents Introduce Fast/Slow Path Two-Tier Filtering

On November 3, 2026, a post titled "The first engineering problem of proactive Agents: Fast/Slow Path two-level filtering" appeared on Juejin. It took up the issue of trigger efficiency for proactive Agents operating in environments such as group chats and code collaboration platforms.

The post argues that once a proactive Agent is connected to a real event stream from these sources, the feed exhibits two harsh characteristics: high noise and a low trigger rate. As the author illustrates, a developer group may exchange several hundred messages in a single day, with casual chatter accounting for more than ninety percent of the volume. The moments that genuinely warrant the Agent taking action, by contrast, might arise only once or twice per day.

To cope with this mismatch, the post proposes a Fast/Slow Path two-level filtering mechanism for proactive Agents. Rather than evaluating every incoming event at full depth, a lightweight fast path screens the stream first, with only the rare candidates that pass the first filter promoted to the more expensive slow path. This staging is intended to keep trigger overhead proportional to the actual number of actions worth taking.

Alongside the argument, the post ships a runnable simulator of eighty lines of code so that developers can reproduce the setup directly and experiment with the filtering behavior themselves. As of this writing, the piece stands as the only discussion of this approach available, and no follow-up implementations or independent evaluations have appeared yet.