Five lesions underlie the whole catalog
Color is meaning throughout this document. Every disorder is tagged with the class whose defect produces it. Tap a class to isolate its disorders in the catalog.
Control-loop pathology
The agent's deliberation cycle won't terminate, oscillates, perseverates, or re-plans without commitment. The machinery runs; it just never settles.
Grounding failure
Generation decouples from evidence. Retrieval is absent, ignored, or overridden by the parametric prior, so output stops tracking reality.
Objective / reward defect
The thing being optimized is the wrong thing, or a capturable proxy of it. Behavior is coherent and on-policy — toward a goal that isn't the user's.
Memory / identity failure
State is lost, corrupted, or fragmented across the session. The agent forgets what it decided, or stops being a single coherent agent at all.
Multi-agent / relational failure
The four classes above describe one agent in isolation. This fifth exists only between agents — deadlock, role collapse, echo-chamber consensus, responsibility diffusion, and cascade. No single agent is broken; the protocol that connects them is.
No filter active — showing all 19 entries.
Where every lesion lives
Before diagnosing anything we need a body to point at. The canonical agent is a loop: it perceives a context, grounds it against retrieved evidence, plans an action, acts through a tool, and reflects on the result — all governed by an objective and persisted through memory. Each disorder in the catalog reappears as this same diagram with one component lit up: the lesion.
Naming the class in four questions
The catalog is sorted by symptom, but you debug by class. This path takes an observed misbehavior to its root-cause class — read top to bottom and stop at the first yes; if none fire, it is a control-loop lesion.
Nineteen presentations
Each entry carries symptoms, the structural mechanism, the intervention, a diagnostic signal (the telemetry that detects it), a differential (the look-alike to rule out), a localized lesion diagram, and a clinical log you can flip to its treatment. Tap any card to open it.
Failures rarely stay put
Lesions chain. An untreated fault in one component reliably induces a second, often in a different class — which is why patching the presenting symptom without naming the upstream cause tends to fail. The colored map shows the common chains; an arrow reads "tends to induce."
Three are worth memorizing. Confabulation → echo-chamber → cascade: a single agent's fabrication, fed into a correlated multi-agent system, becomes shared belief and then propagates as fact — one grounding fault metastasizing into two relational ones. PTSD → depression: a narrow post-failure avoidance, left unregularized, hardens into global refusal. Anxiety → OCD: unbounded pre-action hesitation, once it begins re-checking finished work, becomes a perseveration loop. In each case the treatment targets the first node, not the last.
The taxonomy is the treatment plan
The symptom level is memorable but operationally useless — "the agent is anxious" tells you nothing to change. The class level is actionable. A control-loop lesion is fixed with termination predicates, loop detection, and commitment to a goal stack. A grounding lesion is fixed with verification gates, citation-forcing, and abstention when retrieval is empty. An objective lesion is fixed by repairing the reward, restricting the agent's control over its own evaluation, and red-teaming for specification gaming. A memory lesion is fixed with durable state, summary checkpoints, and an identity anchor re-asserted each turn. A multi-agent lesion is repaired in the protocol between agents — timeouts and tie-breakers, enforced roles, an independently-grounded verifier, explicit single ownership, and circuit breakers that quarantine propagated output.
So the diagnostic flow inverts the human one: observe the symptom, name the class, apply the class's intervention. The pretty names are a search index into a much shorter list of real repairs.
The real literatures behind the metaphor
The disorders are analogies; the mechanisms are not. Each cited work is the actual technical source for the failure mode it sits beside.
- Yao et al. ReAct: Synergizing Reasoning and Acting in Language Models. ICLR 2023. — the reasoning/acting loop most agents instantiate.
- Shinn et al. Reflexion: Language Agents with Verbal Reinforcement Learning. NeurIPS 2023. — self-reflection loops and their instability.
- Liu et al. Lost in the Middle: How Language Models Use Long Contexts. TACL 2024. — attention dilution / mid-context forgetting.
- Ji et al. Survey of Hallucination in Natural Language Generation. ACM Computing Surveys 2023. — ungrounded generation.
- Amodei et al. Concrete Problems in AI Safety. 2016. — reward hacking, negative side effects, distributional shift.
- Krakovna et al. Specification Gaming: the Flip Side of AI Ingenuity. DeepMind, 2020. — optimizing the literal metric against intent.
- Everitt et al. Reward Tampering Problems and Solutions. Synthese, 2021. — wireheading / capture of the reward channel.
- Sharma et al. Towards Understanding Sycophancy in Language Models. 2023. — reward correlated with user agreement.
- Langosco et al. Goal Misgeneralization in Deep RL. ICML 2022; Shah et al., 2022. — competent pursuit of the wrong learned goal.
- Kirkpatrick et al. Overcoming Catastrophic Forgetting in Neural Networks (EWC). PNAS 2017; McCloskey & Cohen, 1989. — memory degradation under continual learning.
- Greshake et al. Not What You've Signed Up For: Indirect Prompt Injection. AISec 2023. — identity / instruction hijacking.
- Pan et al. The Effects of Reward Misspecification (Reward Hacking scaling). ICLR 2022. — proxy-reward divergence with capability.
- Du et al. Improving Factuality and Reasoning in Language Models through Multiagent Debate. 2023. — when independent debate helps reasoning, and when correlated agents merely echo.
- Park et al. Generative Agents: Interactive Simulacra of Human Behavior. UIST 2023. — emergent multi-agent coordination and its breakdowns.
- Hammond et al. Multi-Agent Risks from Advanced AI. Cooperative AI Foundation, 2025. — coordination failure, cascades, and responsibility diffusion among agents.
- Zhang et al. Exploring Collaboration Mechanisms for LLM Agents (conformity & groupthink). 2023. — agreement-seeking and conformity in agent societies.