434
Analyzed Sessions
Work / Case study
Across 434 multi-turn sessions in Claude Code, OpenAI Codex, Antigravity, and Cursor, autonomous coding models repeatedly failed in the same five ways. This case study documents an involuntary telemetry, Thrash Index, and rule-synthesis engine built to turn developer friction into deterministic behavioral constraints.
Analyzed Sessions
Message Turns
Tool Invocations
Friction Clustered
Working full-time with autonomous coding agents reveals a consistent pattern: model capabilities are remarkable, but cross-session operational memory is zero. An agent that breaks UI touch targets or creates Next.js hydration loops at 2:00 PM will make that exact same mistake at 8:00 PM in a fresh session.
Manual prompt engineering and constant supervision cause severe cognitive fatigue. I needed a system that observed every model turn invisibly, quantified when the model was flailing in unproductive loops, and automatically extracted permanent constraints to protect the codebase.
To detect when an agent is flailing rather than making progress, the pipeline calculates the Thrash Index: the ratio of failed tool executions, user interventions, and file rollbacks relative to total session turns.
Sessions scoring above 15% indicate severe context exhaustion or prompt derailment. Rather than continuing to burn tokens on speculative repairs, the system triggers automated session compaction and alerts the developer.