[rockfordlhotka]

Summary

• Removed the active-thread floor. A follow-up on a 3+-turn thread no longer goes to Balanced just because the thread exists. It inherits Balanced (the existing inherited-tier rule) only when a recent turn earned it, so small talk stays Low past turn 3.
• IntrinsicTier is captured before the thread-state rules. The content floors (research question, balanced-floor keyword) still count toward it. The active-subagent floor and inheritance no longer do, so a Balanced thread decays after MaxTurnsPerSession turns that neither earn it nor do work.
• Turns that do real work record Balanced. At the end of a user turn, UserMessageHandler.EarnedTier raises the turn's history entry to Balanced when its tool ledger has a call that counts as thread work (ToolSideEffects.IsThreadWork). That is any call except memory, working-memory, skill and tool-guide reads and the agent's own bookkeeping. Mid-turn escalation only fires on Low-routed runs, so without this a Balanced turn that edited a deck recorded Low and the thread decayed mid-task.
• The active-subagent-floor is unchanged. TierRoutingRules.ActiveThreadFloor stays so older routing-log entries remain readable.

Routing-log analysis (prod, 10/10–10/21)

• active-thread-floor decided 59 of 131 rule-logged user turns, more than any other rule. About 8 of those 59 were casual: the propane message, the health updates, the evening plans, and the trivia probes.
• Raw tool use is not a usable signal. All 274 Low user turns with a toolCallCount made at least one call, because every turn opens with search_memory / search_working_memory / get_from_working_memory. That's why IsThreadWork excludes context reads.
• The Agent replies to injected memory instead of recent prompt on short user messages #383 defenses that don't depend on tier stay in place: the short-message BM25 gate (≤30 chars) and the memory-summary reply guard (≤120 chars, on by default). The Low model is now gpt-5.6-luna.

Test plan

• dotnet test RockBot.slnx: all pass
• New: a casual session stays Low past turn 3; a Balanced turn's follow-ups inherit Balanced and then decay to Low; the active-subagent floor is not part of IntrinsicTier; IsThreadWork classification; EarnedTier
• Live: a casual exchange plus "I'll find out soon" logs rule=score-band tier=Low and the reply continues the thread (Agent replies to injected memory instead of recent prompt on short user messages #383 shape)
• Live: a work request, then short follow-ups, inherit Balanced and decay after three trivial turns

Closes #729

🤖 Generated with Claude Code

[Copilot]

🟡 Changes recommended

Worker delegation is excluded from earned-tier tracking, allowing worker-backed tasks to lose Balanced inheritance despite continuing substantive work.

1 open issue

• Count spawn_workers as thread work for tier tracking · New

What changed in this PR

This PR updates RockBot’s thread-aware model routing so casual conversations stay Low and Balanced inheritance expires when recent turns neither earn a higher tier nor perform substantive work.

Changes:

• Removes the active-thread floor and captures intrinsic tier before thread-state rules.
• Records substantive tool work as earning at least Balanced for subsequent turns.
• Adds routing, decay, and tool-classification tests and updates routing documentation.

File	Description
tests/​RockBot.Llm.Tests/​ThreadAwareTierRoutingTests.cs	Tests casual routing, inheritance, decay, and content floors.
tests/​RockBot.Llm.Tests/​KeywordTierSelectorTests.cs	Updates expectations for earned-tier inheritance.
tests/​RockBot.Host.Tests/​ToolSideEffectsTests.cs	Tests thread-work classification.
tests/​RockBot.Host.Tests/​SessionTierHistoryTests.cs	Tests Balanced-to-Low decay.
tests/​RockBot.Agent.Tests/​TurnEarnedTierTests.cs	Adds earned-tier calculation tests.
src/​RockBot.Llm/​KeywordTierSelector.cs	Removes the active-thread floor and repositions intrinsic-tier capture.
src/​RockBot.Host/​ToolSideEffects.cs	Adds substantive thread-work classification.
src/​RockBot.Host/​SessionTierHistory.cs	Documents work-based history promotion.
src/​RockBot.Host.Abstractions/​ShortMessageHeuristics.cs	Documents removal of the active-thread floor.
src/​RockBot.Host.Abstractions/​ILlmTierSelector.cs	Clarifies routing contracts and retains the legacy rule identifier.
src/​RockBot.Agent/​UserMessageHandler.cs	Raises recorded tiers based on completed-turn work.

_{Review effort: Balanced}

[rockfordlhotka]

Fixed in 3fa3b4b. IsThreadWork now returns true for spawn_workers (snake_case and PascalCase). Its side-effect classification is unchanged; IsBookkeeping and IsSideEffecting still exclude it. Added regression coverage: ToolSideEffectsTests.ThreadWork rows for both name forms, and TurnEarnedTierTests.WorkerBatchOnly_EarnsBalanced, which also asserts that spawn_workers is still not side-effecting.