A no-progress 'circuit breaker' that auto-halts a coding agent stuck repeating failed actions — triggered by looping, not by a dollar/token cap
Developers running Claude Code / Codex autonomously report agents falling into doom loops: re-running tests against a small self-inflicted error (missing import, wrong param) and burning enormous token volume with zero progress. The specific pain is detecting and halting on repeated failed/no-diff actions, which current guardrails treat as a weak heuristic bolted onto a deterministic budget cap that fires a turn or more too late. The wedge is loop/no-progress detection as the PRIMARY halt trigger, independent of spend — and crucially one that catches paraphrased retries, not just exact-match repeats.
Distinct from a budget cap or cost dashboard — users say those fire too late. The defensible product leads with semantic detection (repeated edit-test-fail cycles, no-diff progress over N turns) and halts immediately. The hard part is catching paraphrased retry loops, because naive exact-hash matching misses them; that detection is the moat, not the dashboard.
landscape (3 existing solutions)
Existing guardrails anchor on dollar/token budget caps and treat loop detection as an afterthought, so they halt only after the waste happens; nothing leads with semantic 'agent is repeating failed actions / making no progress' detection as the primary, immediate trigger.