refactor(agent): trim obsolete loop surfaces

packages/compact/compact-basic/src/index.ts

@@ -112,6 +112,7 @@ export class BasicCompactService extends CompactService {
 
   private readonly warnedPressureConfigTargets = new Set<string>()
   private readonly overflowRetries = new WeakMap<Agent, number>()
+  private readonly overflowAgents = new WeakMap<Session, Agent>()
 
   constructor(ctx: Context, config: BasicCompactConfig = {}) {
     super(ctx)
@@ -158,6 +159,14 @@ export class BasicCompactService extends CompactService {
       this.overflowRetries.delete(agent)
     })
 
+    // A successful response starts a fresh overflow-recovery sequence even
+    // when tool calls continue the same turn into another request.
+    ctx.on('session/event', (session, event) => {
+      if (event.type !== 'assistant/message') return
+      const agent = this.overflowAgents.get(session)
+      if (agent !== undefined) this.overflowRetries.delete(agent)
+    })
+
     ctx.on('agent/request-error', async (
       agent,
       _turn,
@@ -168,6 +177,7 @@ export class BasicCompactService extends CompactService {
       next,
     ) => {
       if (failure.code !== CONTEXT_WINDOW_EXCEEDED_CODE || signal.aborted) return next()
+      this.overflowAgents.set(agent.session, agent)
       const target = routedTarget(agent.session)
       if (target === undefined) return next()
       const policy = resolveTargetPolicy(this.config, target)

packages/compact/compact-basic/src/region.ts

@@ -199,7 +199,7 @@ function buildSummarizationInput(
   return {
     ...header?.system === undefined ? {} : { system: header.system },
     ...header?.tools === undefined ? {} : { tools: header.tools },
-    messages: [...header?.messagePrefix ?? [], ...regionMessages],
+    messages: regionMessages,
   }
 }
 

packages/compact/compact-basic/tests/compact-loop-repro.spec.ts

@@ -389,7 +389,6 @@ describe('context-overflow recovery across the real loop and compact-basic', ()
         agentOptions: { provider: 'mock', model: 'mock' },
       })
       agent.followup([{ type: 'text', text: 'continue from history' }])
-      await expect.poll(() => adapter.conversationRequests.length).toBe(3)
       await agent.whenIdle()
 
       expect(adapter.conversationRequests).toHaveLength(3)