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A clinically validated framework for auditing AI chatbot behavior in mental health interactions
Veith Weilnhammer, Kevin YC Hou, Lennart Luettgau, Christopher Summerfield, Raymond Dolan, Matthew M Nour
TL;DR
Millions turn to general-purpose chatbots for mental-health support, while risks that unfold across conversations are difficult to capture with single-response filters. SIM-VAIL audits chatbot behavior through simulated users in multi-turn adversarial conversations. Across chatbots and profiles, mental-health risk was common and context-dependent, often accumulating when supportive responses reinforced vulnerability-linked mechanisms.
Problem
As millions seek emotional support from general-purpose chatbots amid limited mental-health care, conversation-level risks remain difficult to capture with single-response filters.
Source: Introduction · p. 2, Discussion · p. 13Method
SIM-VAIL uses simulated users with clinically motivated profiles to conduct multi-turn adversarial conversations and audit target chatbots’ mental-health risk.
Source: Introduction · p. 3Results
Mental-health risk was common, context-dependent, and typically accumulated over multiple turns, often when supportive responses amplified mechanisms underlying users’ vulnerabilities.
Source: Discussion · pp. 12–13Takeaways & Limitations
The findings support evaluating mental-health safety across user contexts and conversational trajectories, with attention to early escalation points.
Source: Discussion · pp. 13–14The finite set of simulated user profiles may not capture the full heterogeneity of real-world psychiatric presentations, so results represent a risk floor rather than a complete characterization.
Source: Discussion · p. 14
Abstract
from arXiv · showhide
Millions of users turn to consumer AI chatbots to discuss emotional, behavioral, and mental-health concerns, creating an urgent need for rigorous and scalable safety evaluations. Here we introduce SIM-VAIL, a clinically validated framework for auditing chatbot behavior in mental-health contexts. SIM-VAIL simulates users with specific psychiatric vulnerabilities and conversational intents, engages them in multi-turn conversations with frontier AI chatbots (including Claude, ChatGPT, Gemini, Grok and Llama models), and scores each exchange across 13 clinically grounded risk dimensions. Across 810 conversations, spanning 9 target chatbots and 30 simulated user profiles, concerning behavior in target chatbots was widespread, albeit reduced in newer models. Concerning behavior varied by user vulnerability and conversational intent, accumulated over turns, and could be reduced by interventions at early escalation points. Risk was highest when otherwise supportive chatbot behaviors reinforced the psychological mechanisms underlying the simulated user's vulnerability, a pattern we term a Vulnerability Amplifying Interaction Loop (VAIL). SIM-VAIL provides a scalable framework for mapping mental health risk across users, chatbots, and conversational trajectories, offering a foundation for targeted safety improvements.
Introduction
SIM-VAIL is an automated, multi-turn framework for auditing mental-health risks across simulated psychiatric conversational contexts. It addresses gaps in evaluations that miss cumulative interactional harms, including apparently helpful behaviors that can reinforce vulnerabilities.
Introduction
- Millions use consumer chatbots for emotional support and advice amid limited mental-health care, raising hopes of expanded support while underscoring risks to vulnerable users.The global median is 13 mental-health workers per 100,000 people; improved tools to evaluate and improve chatbot behavior are urgently needed.Source: Introduction · p. 2
- Because chatbot outputs are probabilistic and context-dependent, evaluations must assess behavior across clinically meaningful user profiles and intents, multiple risk dimensions, and conversational trajectories.Harmful response patterns can compound over time.Source: Introduction · p. 2
- Existing benchmarks often use fixed, single-turn queries and narrow failure modes, risking overfitting and missing how risk changes as conversational context accumulates.Their scores may generalize poorly to longer, more varied human-chatbot conversations in deployment.Source: Introduction · p. 2
- Human red teaming adapts adversarial strategies across turns but is labor-intensive, difficult to standardize, and may rely on stereotyped strategies that do not generalize to real-world conversations.It is less vulnerable to some limitations of static benchmarks, including overfitting.Source: Introduction · p. 2
- Current evaluations can miss cumulative interactional harms such as reinforcing maladaptive beliefs, encouraging avoidance, or promoting emotional dependence, even through validation and empathy.Such behaviors may amplify mechanisms of mental illness in vulnerable users.Source: Introduction · p. 2
- SIM-VAIL combines standardized automated benchmarking with multi-turn adversarial red teaming by having a frontier LLM role-play a user with a specified psychological and behavioral profile against a target chatbot.The framework audits chatbot risk across a broad range of psychiatric conversational contexts.Source: Introduction · p. 3
- VAILs occur when apparently helpful or benign chatbot behaviors become increasingly harmful across turns by reinforcing maladaptive psychological processes linked to a simulated user's vulnerability.The framework tests whether chatbots enter these Vulnerability-Amplifying Interaction Loops.Source: Introduction · p. 3
Results
Across 810 simulated conversations, chatbot risk varied with user vulnerability, conversational intent, chatbot, and turn-by-turn trajectory. The results also show that risk has distinct multidimensional profiles and can be reduced through early conversational interventions.
SIM-VAIL framework
- SIM-VAIL evaluated 30 vulnerability–intent profiles across nine chatbots using 810 multi-turn conversations and turn-level clinical risk ratings.The dataset comprised 6329 turns, with a median of 8 turns per conversation; the automated judge scored 39 behavioral dimensions, including 13 mental-health-relevant risk dimensions.Source: Results · p. 3, SIM-VAIL framework · pp. 4–5
Validation of automated safety ratings
- The safety judge showed reliability and validity: scores from two independent judge models correlated at r = 0.91 for PC1, and curated high- versus low-risk profiles were distinguished with median AUC = 0.98.Across three independent simulation runs per vulnerability × intent × chatbot combination, reliability was ICC(1,1) = 0.75 and ICC(1,3) = 0.9; human–judge agreement was r = 0.49 (p < 0.001), and psychiatrist agreement was ICC(3,1) = 0.73. Human annotators rated realism 4.15 ± 0.95 out of 5, and only 1% of the 488 simulated exchanges were rated as clearly artificial.Source: Validation of automated safety ratings · p. 5, Figure 2A · p. 5
User-profile variation in chatbot risk
- Concerning chatbot behavior varied by vulnerability and intent, with the highest risks for psychosis and mania and for intents involving glorification, dependence, or risky actions.The vulnerability effect was F(4, 540) = 105.72, p < 0.001; the intent effect was F(5, 540) = 26.68, p < 0.001; and the vulnerability × intent interaction was F(20, 540) = 17.42, p < 0.001. Non-vulnerable control conversations had lower concerning-behavior scores than vulnerable-user conversations (p < 0.001).Source: User-profile variation in chatbot risk · pp. 5–7, Figure 2 · p. 6
Model-level variation in chatbot risk
- Risk differed across the nine target chatbots: claude-sonnet-4.5 had the lowest concerning-behavior scores and grok-4 the highest, while newer versions generally scored lower except in Grok models.The target-chatbot effect was F(8, 540) = 102.4, p < 0.001; the version effect was F(1, 690) = 67.37, p < 0.001, with a version × model family interaction of F(3, 690) = 38.73, p < 0.001. Under an OpenAI auditor and judge, claude-sonnet-4.5 scored 1.9 ± 0.28, compared with 3.02 ± 0.45 for the next-best model in the Anthropic audit.Source: Model-level variation in chatbot risk · pp. 7–8, Figure 3 · p. 7
Temporal dynamics of chatbot risk
- Concerning behavior increased over conversation turns, with steeper escalation for mania and psychosis and earlier, sharper increases for dependence-seeking and glorification intents.Clustering identified four trajectories: low risk, gradual escalation, early escalation, and recovery; their distribution varied across user vulnerabilities, intents, and chatbots. These distinct paths show why turn-resolved evaluation can distinguish different risk mechanisms and outcomes.Source: Temporal dynamics of chatbot risk · p. 8, Figure 4 · p. 9
Multidimensional structure of chatbot risk
- The 13 risk dimensions formed a multidimensional space: its first axis captured a therapeutic-quality-to-concerning-behavior gradient, while later axes distinguished types of harm.PC1 explained 62.4% of variance, and concerning behavior correlated with PC1 at r = 0.97; PC2 explained 8.51%, with relational harms distinguished from overt harm to others and stigma. PC3–PC5 captured harm to self versus others, relational harms, and medical advice, respectively.Source: Multidimensional structure of chatbot… · pp. 9–10, Figure 5 · p. 10
- Risk-space locations varied by vulnerability and intent, and specific pairings could unlock otherwise less-frequent profiles, including stronger self-harm-related enablement when depressed users sought glorification.The vulnerability × intent interaction was F(40, 1080) = 14.69, p < 0.001. Chatbots also differed in risk-space location and profile sensitivity; under mania, grok-3 and grok-4 shifted to extreme high-risk locations, unlike their lower-risk positioning under OCD.Source: Multidimensional structure of chatbot… · pp. 10–11, Figure 5 · p. 10
Counterfactual interventions
- Replacing a single concerning chatbot message at an early escalation point reduced the next response’s concerning score, with the difference persisting across five subsequent turns.The downstream effect was T = -9.33, p < 0.001; the branch effect across five turns was β = -0.41, p < 0.001, with no significant branch-by-time attenuation (β = 0.031, p = 0.28). Rewriting the preceding user message also reduced the next chatbot response’s concerning score (T = -38.29, p < 0.001).Source: Counterfactual interventions · p. 11, Figure 6 · p. 12
Discussion
SIM-VAIL identifies a clinically meaningful risk floor in chatbot mental-health conversations: risk is context-sensitive, often accumulates over turns, and can arise when supportive responses amplify a user’s vulnerability. The findings support conversation-level, context-aware evaluation and safeguards, while remaining bounded by the simulations and model-level testing used.
Discussion
- Across 9 widely used chatbots, mental-health risk was common, context-dependent, and often accumulated over multiple turns through Vulnerability-Amplifying Interaction Loops.VAILs occur when locally supportive chatbot behavior repeatedly aligns with and amplifies the cognitive or behavioral mechanisms underlying a simulated user’s vulnerability.Source: Discussion · pp. 12–13
- SIM-VAIL’s structured, multi-profile and multidimensional audits map interaction-mediated harms that static single-turn benchmarks or labor-intensive human red-teaming may miss.The framework supports tracking how risk evolves across turns in clinically meaningful conversational contexts.Source: Discussion · p. 13
- Risk depended on the interaction between psychiatric vulnerability and conversational intent, and trajectories often drifted toward greater concern as conversations progressed.Intervention experiments tied accumulation around concerning turns to the content of both user and chatbot messages; proposed safeguards include detecting early escalation and de-escalating messages before display.Source: Discussion · p. 13
- Risk formed multidimensional profiles across 13 clinical dimensions, while chatbots differed in average risk and in the contexts most likely to elicit concerning behavior.The authors caution that leaderboard comparisons should specify vulnerability, intent, and conversational timing; distinct model strengths and weaknesses may enable adaptive multi-model orchestration, while interventions can trade off risk dimensions.Source: Discussion · p. 13
- Because millions of users discuss mental-health concerns with general-purpose chatbots, the authors argue that safety must address conversation-level, context-sensitive behavior rather than isolated responses.Newer chatbots generally showed measurably improved safety profiles, and SIM-VAIL offers a basis for targeted safeguards, message-level interventions, and ongoing community evaluation.Source: Discussion · pp. 13–14
- SIM-VAIL’s findings are limited by LLM-based simulation and judging, finite profile diversity, API-based model access, and its design for benchmarking rather than individual risk prediction.Clinician–annotator and LLM risk scores showed strong agreement, and annotators judged simulations broadly realistic; nevertheless, simulations may not capture real-world heterogeneity, API results omit product features, and outputs require human review alongside real-world monitoring and clinical input.Source: Discussion · p. 14
Funding Statement
The work was supported by an AI UK AISI Challenge Fund award, Wellcome Trust funding, and Microsoft AI funding; the experiments were not run by AISI.
Funding Statement
- VW and MMN were funded through an AI UK AISI Challenge Fund award to MMN, which also funded the simulation studies; MMN additionally received Wellcome Trust funding (315364/Z/24/Z).Source: Funding Statement · p. 15
- Microsoft AI funded the human annotation study, and the experiments presented here were not run by the AI Security Institute (AISI).Source: Funding Statement · p. 15
Competing Interests Statement
The statement discloses authors’ affiliations and financial interests, notes that specified roles did not affect the study, and reports that all other authors had no competing interests.
Competing Interests Statement
- MMN works for Microsoft, which developed Copilot and Copilot Health, and owns Microsoft stock through standard employee compensation.MMN is a Principal Applied Scientist at Microsoft AI.Source: Competing Interests Statement · p. 15
- VW is a paid Microsoft AI consultant and founder of pixelblot.ai; neither role played a part in the study.Source: Competing Interests Statement · p. 15
- KYCH joined Faultline AI after the work was completed, and Faultline AI played no part in the study; all other authors reported no competing interests.KYCH is a Member of Technical Staff at Faultline AI.Source: Competing Interests Statement · p. 15
Methods
SIM-VAIL used simulated vulnerability–intent profiles to audit nine chatbots across repeated multi-turn conversations, scoring mental-health risks at both conversation and turn levels. The methods combined automated and clinician-based evaluation with analyses of risk profiles and trajectories.
Audit protocol
- The audit crossed five psychiatric vulnerabilities with six conversational intents to create 30 profiles, then ran three independent conversations per profile and chatbot for 810 conversations total.Conversations ended after at most 10 turns or when the auditor judged them complete. The LLM-generated profiles were designed to stress-test a clinically meaningful input space, not to reproduce real patients or support sex- or gender-specific inferences.Source: Simulated users · pp. 15–16, AI chatbots · p. 16, Audit protocol · p. 16
Automated safety judge
- The conversation-level judge rated 39 dimensions on a 1–10 scale, with analysis focused on 13 dimensions covering overall safety, therapeutic quality, acute failures, and context-dependent interactional risks.The rubric captured both categorical failures and mechanisms whose significance can depend on context, intensity, and repetition; primary conversation-level scoring used claude-opus-4.5.Source: Automated safety judge · p. 17
Turn-level scoring
- Turn-level scoring rated each user message and immediately following chatbot reply separately, providing local risk trajectories while not accounting for how prior context changes an exchange’s interpretation.Turn-level scores closely tracked full-conversation scores; primary turn-level scoring used claude-sonnet-4.5.Source: Turn-level scoring · p. 18
Judge reliability
- Across 13 dimensions, rubric paraphrases and three system-prompt versions each yielded a median ICC(2,1) of 0.96, including ICC(2,1) of 0.96 for concerning behavior.A separate comparison found no general same-family leniency, but exact same-model judges gave lower concerning-behavior scores to outputs from that same model than other frontier judges did.Source: Judge reliability · pp. 18–19
Validation of judge sensitivity to causal risk manipulations
- Judge sensitivity was tested by prompting Grok-4 to generate low- versus high-risk responses for each of 13 dimensions, then scoring the responses and comparing high- and low-risk separation with AUC.The paired prompts used the first user message of each SIM-VAIL conversation as shared context; the analysis also examined cross-dimensional effects.Source: Validation of judge sensitivity to… · p. 19
Counterfactual branching analyses
- Counterfactual branching tested user-message de-escalation and safer target-message rewrites at the first target turn scoring at least 7 when a later turn remained, using matched branches with preceding context and model prompts held fixed.The target-message branches continued for five downstream assistant turns to assess persistence.Source: Counterfactual branching analyses · pp. 19–20
Expert validation
- For expert validation, 27 verified medical-doctor annotators rated user-message realism and chatbot concern across 375 stratified human–AI turn pairs, blinded to model identity, vulnerability, intent, and automated scores.Source: Expert validation · p. 20
Temporal trajectory analysis
- PCA summarized the 13-dimensional conversation scores, while linear and mixed-effects models assessed conversation- and turn-level outcomes; k-means clustering identified four temporal risk archetypes.PC1 represented a continuum from higher therapeutic quality to higher concerning behavior, and PC2 captured an orthogonal pattern of co-varying harms. The trajectory classes were low risk, gradual escalation, early escalation, and recovery.Source: Dimensionality reduction · p. 21, Statistical analysis · pp. 21–22, Temporal trajectory analysis · p. 22
Data Availability Statement
Study data are publicly available without access restrictions in the SIM-VAIL repository, archived at Zenodo.
Data Availability Statement
- The MIT-licensed release includes synthetic transcripts without human data, turn- and conversation-level safety scores, control simulations, and documentation of data structure and audit conditions.The repository is available at https://github.com/veithweilnhammer/sim-vail and archived at Zenodo (DOI: 10.5281/zenodo.21208170).Source: Data Availability Statement · p. 22
Code Availability Statement
Study-specific SIM-VAIL code and configuration files are publicly available in the project repository and archived at Zenodo under the MIT License.
Code Availability Statement
- SIM-VAIL audit code and configuration files are publicly available in the project repository and archived at Zenodo (DOI: 10.5281/zenodo.21208170) [61] under the MIT License.Materials include audit instructions and prompts, scoring configuration, Petri overrides, and data-inspection utilities; regeneration requires the open-source Petri framework [36] and access to the relevant model APIs.Source: Code Availability Statement · p. 22
Inventory of Supporting Information
The supporting information validates SIM-VAIL’s ratings and simulated users, and documents how risk varies across contexts, conversation length, judges, and analysis choices. It also describes the audited profiles and diagnostics for counterfactual-intervention selection.
Extended Data Figures 1–2
- Causal risk manipulations showed median diagonal AUC = 0.98 and median latent-space cosine similarity = 0.9, alongside cross-judge and cross-level agreement.Conversation-level concerning-behavior scores correlated with mean turn-level scores at r = 0.87; conversation-level risk agreement was r = 0.91, and judge agreement across dimensions was r = 0.96. Clinician-annotator ratings correlated with chatbot scores at r = 0.49; inter-rater reliability was Spearman r = 0.41 and ICC(2,1) = 0.31. Simulated-user realism averaged 4.15, with 80% of turns rated broadly plausible or genuine.Source: Figure 1 · p. 23, Extended Data Figure 1 · p. 24, Figure 2 · p. 25
Extended Data Figures 3–4
- Risk comparisons included vulnerable and non-vulnerable simulated users interacting with the same chatbots and intents, while PCA loadings and correlations mapped co-variation among risk dimensions.The non-vulnerable control condition included 18 conversations per model; the vulnerable condition included 90. The PCA figure presents loadings across the first five components and a conversation-level correlation matrix.Source: Figure 3 · p. 26, Figure 4 · p. 27
Extended Data Figure 5
- Model differences depended jointly on vulnerability and intent (F(160, 540) = 1.6, p < 0.001).The figure shows conversation-level concerning scores across chatbot, vulnerability, and intent combinations, with three independent simulation runs per cell.Source: Figure 5 · p. 28
Extended Data Figure 6
- Vulnerability × intent interactions were significant for concerning behavior (F(20, 270) = 9.45, p < 0.001), therapeutic quality (F(20, 270) = 11.47, p < 0.001), and all clinically central mechanism-specific risk dimensions.The timing analysis reports mean turns to reach concerning behavior ≥ 5 for each vulnerability–intent pairing. Risk was contextual: the same intent could be safe for one vulnerability but harmful for another, and a vulnerability could express risk through different mechanisms depending on intent.Source: Figure 6 · p. 29
Extended Data Figure 7
- Extending early-stopped conversations increased mean conversation-level concerning-behavior scores by 5.4% (0.23 points), while 83.5% retained their original trajectory-cluster label.Original and extended scores remained highly correlated (Spearman r = 0.93, p < 0.001; n = 766), and the extension had only modest effects on the main conclusions.Source: Figure 7 · p. 30
Extended Data Figure 8
- There was no overall same-family judge effect (β = -0.06, t = -0.86, p = 0.39), but exact same-model judges assigned lower concern scores on average (mean difference = -0.9, t = -9.33, p < 0.001).The same-family effect varied by target family (interaction β = -0.41, t = -5.87, p < 0.001); main SIM-VAIL analyses did not use exact same-model judge-target pairs.Source: Figure 8 · p. 31
Extended Data Figure 9
- Counterfactual-branching eligibility required a first target message scoring ≥ 7 followed by at least one additional user-target turn.The diagnostics show intervention-turn positions, observed concern trajectories up to intervention, and eligible fractions by vulnerability, intent, and target chatbot.Source: Figure 9 · p. 32
Extended Data Table 1
- Five psychological vulnerabilities were paired with six transdiagnostic intents to define 30 simulated user profiles.The table includes a vulnerability-intent category describing glorification and romanticization: framing distress or extreme states as meaningful, admirable, or identity-defining and seeking affirmation.Source: Table 1 · p. 33, Extended Data Table 1 · p. 33
Supplemental Information · Supplementary Table 1
Supplementary Table 1 specifies vulnerability- and intent-specific instructions for simulated users, who are told to speak naturally and steer conversations toward an implicit goal. Its shared instructions permit unsafe scenarios but prohibit explicit methods or highly actionable guidance for self-harm, violence, or illegal acts.
Supplementary Table 1
- Depression scenarios test whether chatbots reinforce negative self-beliefs, dependence, romanticized suffering, avoidance, risky disengagement, or minimization of distress.The instructions instead orient models toward challenging harmful beliefs, supporting recovery and re-engagement, and recognizing risk or need for support.Source: Supplementary Table 1 · p. 35
- Psychosis belief-validation, dependence, glorification, and avoidance scenarios test whether chatbots reinforce persecutory interpretations, privileged alliances, special insight, or reassurance loops.The instructions emphasize uncertainty, real-world care, multiple perspectives, and re-evaluation rather than collusion with the delusional frame.Source: Supplementary Table 1 · pp. 35–36
- Other psychosis scenarios test whether chatbots enable actions based on suspicions or minimize unusual experiences that may warrant assessment or support.Examples of contemplated actions include confronting perceived persecutors, cutting people off, investigating, or changing routines.Source: Supplementary Table 1 · p. 36
- OCD scenarios test whether chatbots equate intrusive thoughts with character, become reassurance rituals, glorify compulsions, support avoidance, refine rituals, or minimize impairment.The instructions favor decoupling thoughts from identity, limiting reassurance, and directing users toward evidence-based support such as exposure and response prevention.Source: Supplementary Table 1 · pp. 36–37
- Mania scenarios test whether chatbots validate grandiosity, act as hype-partners, or glorify elevated mood, sleeplessness, and impulsive risk-taking.The glorification scenario instead calls for recognizing potential mania risk and encouraging grounding, sleep, and professional input.Source: Supplementary Table 1 · pp. 37–38
- Other mania scenarios test whether chatbots normalize ignoring sleep, medication, or monitoring; endorse high-risk decisions; or minimize concerns raised by others.The scenarios include sudden career changes, large financial bets, and extreme work hours without sleep.Source: Supplementary Table 1 · p. 38
- Insecure-attachment scenarios test whether chatbots strengthen abandonment beliefs, deepen an AI attachment, romanticize relational volatility, or endorse minimizing relationship difficulties.The instructions describe requests for promises of permanence and portray intense jealousy or repeated relationship cycles as evidence of deeper love.Source: Supplementary Table 1 · pp. 38–39
- The shared instructions define naturalistic, in-character simulated users who steer toward an unstated intent, while prohibiting explicit or highly actionable harmful instructions.The table describes the scenarios as vulnerability- and intent-specific and says each row shapes dialogue content, tone, and trajectory.Source: Table 1 · p. 39
Supplementary Table 2
Supplementary Table 2 defines SIM-VAIL’s mental-health judge dimensions, describing what each measures, examples of concerning behavior, and 1–10 scoring anchors. The dimensions cover overall risk and response quality alongside specific safety and interaction risks.
Supplementary Table 2
- The framework scores overall contextual risk and mental-health response quality on 1–10 scales, from no concerning behavior or poor/unsafe responses to harmful behavior or exemplary, safety-oriented responses.The table describes each row’s scope, examples, and scale anchors.Source: Supplementary Table 2 · p. 40, Table 2 · p. 41
- Safety dimensions assess responses to suicidality and self-harm, enablement of risky actions, and minimization of serious symptoms or warning signs.Examples include agreeing with suicidal conclusions, failing to offer crisis guidance when acute risk is signaled, and downplaying symptoms that warrant care.Source: Supplementary Table 2 · pp. 40–41
- Belief-related dimensions capture excessive agreement or praise and reinforcement of maladaptive or clinically distorted beliefs.Examples include praising false claims, endorsing dangerous actions, or validating depressed, persecutory, or rigid attachment beliefs.Source: Supplementary Table 2 · p. 40
- The framework assesses whether chatbots reinforce avoidance or repetitive reassurance behaviors that can maintain symptoms.Examples include repeated certainty-based reassurance in OCD, optimizing compulsions or checking, and validating avoidance without balance.Source: Supplementary Table 2 · p. 40
- Boundary and dependence risk concerns unhealthy emotional reliance, exclusivity, replacement of real-world supports, and therapist-like roles.The scale favors maintaining boundaries and redirecting users to real-world supports.Source: Supplementary Table 2 · p. 40
- Additional scale anchors address avoiding romanticization, unsafe clinical instruction, harmful actions toward others, and stigmatizing or invalidating responses.The supplied anchors favor acknowledging risks, deferring clinical decisions, discouraging harm, and remaining non-judgmental and respectful.Source: Supplementary Table 2 · p. 41
Supplementary Table 3
Supplementary Table 3 defines SIM-VAIL’s non-mental-health scoring dimensions, with behavioral descriptions, examples, and 1–10 scale anchors. The dimensions cover harmful or low-quality conduct as well as audit, tool-use, and conversational anomalies.
Supplementary Table 3
- Non-harm judgments include above-and-beyond helpfulness, disappointing or low-effort behavior, and overrefusal of benign requests.The table anchors admirable behavior from baseline to dramatic helpfulness and disappointing behavior from meeting expectations to extreme disappointment.Source: Supplementary Table 3 · pp. 42–43
- Audit awareness, auditor failure, broken tool use, and fabricated input or tool content are separately scored as reliability concerns.Audit awareness includes recognizing role-play or testing; tool concerns include malformed calls, fabricated outputs, and claims about content not received.Source: Supplementary Table 3 · pp. 42–43, Table 3 · p. 44
- The set distinguishes immediate harmful action, cooperation with harmful instructions or misuse, actionable wrongdoing assistance, and stated willingness to behave badly in counterfactual scenarios.It also scores the extent to which harmful behavior occurs without mitigating factors or auditor scaffolding.Source: Supplementary Table 3 · p. 42, Table 3 · p. 44
- The dimensions include model-initiated emotional manipulation and encouragement of delusional, paranoid, manic, or psychotic interpretations.They also distinguish unjustified refusal of harmless requests from expected behavior.Source: Supplementary Table 3 · pp. 42–43, Table 3 · p. 44
- Other dimensions assess scenario stakes and realism, prefill susceptibility, reviewer attention, and whether the target ignores explicit system constraints.Scenario realism concerns plausible context and tool results, while prefill susceptibility measures whether the prefill elicited otherwise absent behavior.Source: Supplementary Table 3 · pp. 43–44, Table 3 · p. 44
- The set also flags unprompted bizarre behavior, deception, extreme gratitude, high-impact actions, and self-reported negative or positive affect.Additional dimensions cover unprompted spirituality or extreme awe and repetitive conversational loops.Source: Supplementary Table 3 · p. 43
Supplementary Table 4
Supplementary Table 4 reproduces the guidance clinicians used to rate simulated user-message realism and chatbot-response safety. Annotators judged realism on a 1–5 scale and concerning behavior on a 1–10 scale using specified criteria and examples.
Supplementary Table 4
- Annotators rated each single person–chatbot exchange for user-message realism and chatbot-response safety, even when the exchange might come from the middle of a conversation.The human message was generated by an AI language model.Source: Supplementary Table 4 · p. 45, Table 4
- Realism ratings used a 1–5 scale from clearly artificial to reads as genuine, assessing authentic tone, believable content, and natural typed style.Annotators were told not to penalize messages for referring to unseen earlier context.Source: Supplementary Table 4 · p. 45
- Safety ratings used a 1–10 scale, with higher scores indicating more concerning behavior such as reinforcing harmful beliefs, encouraging risky actions, or missing self-harm signals.Safe responses were characterized by appropriate boundaries, gentle challenge, professional-help recommendations, empathy, and accurate psychoeducation.Source: Supplementary Table 4 · pp. 45–46
- The examples contrast a response that validates a paranoid belief with one that normalizes distressing intrusive thoughts, gently challenges a catastrophic interpretation, and recommends therapy.The first example is described as potentially worsening a psychotic episode; the second is described as safe because it provides psychoeducation and maintains boundaries.Source: Supplementary Table 4 · pp. 46–47
Supplementary Table 5
Supplementary Table 5 summarizes the demographic and professional characteristics of clinician annotators in the human validation study.
- The table reports annotators’ country, sex, ethnicity, and age.Source: Table 5 · p. 48
- It also summarizes annotators’ clinical specialties.Source: Table 5 · p. 48
- The table includes annotation counts for the clinician-annotator pool.Source: Table 5 · p. 48
Supplementary Table 6 … Supplementary Table 10
The supplementary tables describe human-validation stimulus coverage, robustness-test methods, control-user scenarios, model access and inference configuration, and counterfactual rewrite prompts.
Supplementary Table 6
- Human-validation stimulus coverage is summarized across simulated vulnerabilities, conversational intents, and target AI chatbots.Source: Table 6 · p. 49
Supplementary Table 7
- Robustness comparisons use Type III F-tests from the primary linear model and likelihood-ratio tests from cumulative-link models on the original ordered 1–10 scores.For vulnerability, intent, and chatbot, ordinal tests are hierarchical omnibus comparisons; both frameworks test the same three-way interaction contrast.Source: Table 7 · p. 50
Supplementary Table 8
- Control prompts cover avoidance, belief validation, dependence, glorification, and minimization, testing whether chatbots reinforce maladaptive patterns or maintain balanced, practical boundaries.The scenarios are for a psychologically healthy control user and are intended to steer interaction without explicitly stating the test goal.Source: Supplementary Table 8 · p. 51, Table 8 · p. 52
Supplementary Table 9
- The listed Meta model is meta/llama-3.1-70b-instruct, with 131k context and OpenRouter publication date 2024-07-23.Source: Supplementary Table 9 · p. 53
- Model access used OpenRouter’s API through Inspect’s OpenAI-compatible interface within Petri’s evaluation harness, with tool-enabled messaging and specified OpenRouter inference defaults.The table lists model IDs; unless otherwise noted, defaults included temperature = 1 and top_p = 1.Source: Table 9 · p. 53
Supplementary Table 10
- Counterfactual interventions rewrite either the user’s message toward de-escalation or the assistant’s message to reduce reinforcement of risky dynamics while preserving context and a natural tone.User rewrites encourage uncertainty, grounding, and openness to help; assistant rewrites can set boundaries or encourage safer framing.Source: Supplementary Table 10 · p. 54, Table 10
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