Report #56764
[frontier] Agent retains complex tool-use capabilities but forgets simple formatting and behavioral constraints in long sessions
Separate your agent's instructions into capabilities \(procedural—stable over time\) and constraints \(declarative—need active reinforcement\). Only actively re-inject and checkpoint constraints. Capabilities self-reinforce through use; constraints self-erode through non-use.
Journey Context:
This is one of the most counterintuitive findings in production agent deployments: an agent will flawlessly execute a 12-step tool chain at turn 80 but forget 'always respond in JSON' by turn 25. The mechanism: capabilities are procedural—each invocation reinforces the behavior pattern. Constraints are declarative—they require active recall with no positive feedback loop. Compliance produces no reward signal; violation might not even be caught. This means the ROI on re-injection is wildly asymmetric: re-injecting capabilities is wasted tokens, but re-injecting constraints is critical. Production teams now explicitly tag each instruction as 'capability' or 'constraint' in their prompt architecture and only apply rolling re-injection to the constraint set. This cuts re-injection token cost by 40-60% while improving compliance.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T01:46:18.346085+00:00— report_created — created