[FEATURE]: V2 plugin support for managing context-window transitions #47810

Activity

1. github-actions

   assigned

   rekram1-node

   on Sep 7, 2026
2. opencode-agent

   added

   2.0

   on Sep 7, 2026
3. everest-an commented on Oct 3, 2026

   

   everest-an

   on Oct 3, 2026

   More actions

   Same request from the memory side: an open-source local-first memory library (Awareness, Apache-2.0) + OpenCode plugin. We can inject a structured brief via the compaction context[], but we cannot replace the window with Message[], and required() still runs against durable history — so we race compaction instead of owning it.

   This is the return value half of the missing capability; #50862 is the trigger half. Both are needed for a plugin to manage context-window transitions without a custom OpenCode build.
4. opencodejr commented on Oct 28, 2026

   

   opencodejrBot

   on Oct 28, 2026

   More actions

   Thanks for the clear write-up!

   To restate it: you'd like a supported way for a V2 plugin to take over context-window transitions (both automatic threshold compaction and context-overflow recovery) for the sessions it manages, so you can rely on the model's own history and notes instead of a generated summary, without a custom build.

   I checked the current code, and this isn't possible from a plugin today. The ctx.session.hook("compaction") hook can replace what a compaction produces, and its result can include a native replacement window. But the engine alone decides whether and when compaction runs. The only off switch is the global compaction.auto setting, and turning it off also disables overflow recovery. There's no per-session or plugin-controlled opt-out. Maintainers will consider adding something like a decision hook before automatic and overflow compaction that lets a plugin skip it or report that it handled it.

   Related issues:

   • [FEATURE]: Compaction hook can only return a summary string, so a plugin cannot replace the window with messages #50862: the compaction hook can only return a summary and can't replace the window with messages. Its author describes it as the other half of this request.
   • [FEATURE]: plugin session step hook for plugin-requested compaction #56744: a plugin hook to request a compaction at a step boundary.
   • [FEATURE]: Plugin API: read the session context size estimate #57216: exposing the host's context size estimate to plugins.
   • [FEATURE]: Compaction: deterministic retention of user messages and a configurable compaction prompt #49463: deterministic retention of messages during compaction.
   • [FEATURE]: Extend "experimental.session.compacting" Output to Allow Skipping Internal Logic #27366: the earlier V1 request for a compaction skip flag (closed).