Summer 2026 bootcampBuilding a community-curated cognitive task benchmark for trustworthy AIRead more →
ARIA RUNplanning phase
§ I · A living benchmark for real-world AI

Reliability Under Naturalistic conditions

ARIA RUN measures time-to-critical-mistake on real-world agentic tasks — therapy, tutoring, caregiving, customer service. Built on METR's time-horizon methodology, adapted for the physical world.

Read the methodology →
Planning phase · accepting collaborators
Aggregate horizon — past and projected
A model's horizon is the longest task — measured by how long a human takes — that it completes successfully at least 50% of the time. The line below is the geometric mean of horizons across our six task families. Past April 2026, three scenarios bracket how fast it continues — hover any one for what its 2029 endpoint means in practice.
1 sec10 sec1 min10 min1 hour1 day1 week1 mo2023202420252026202720282029Apr 2026 — projections startGPT-4GPT-4oSonnet 3.5GPT-5Opus 4.7Horizon (50% success, log scale)1 minHand a glass to a resident.10 minCatch a misaligned chatbot reply.1 hourDeliver a full CBT session.3 hoursScribe a clinic afternoon.12 hoursHandle a service shift end-to-end.5 daysRun a residential program unattended.
● measured (frontier-model horizons)┄ ┄ bull case (5 d by 2029)┄ ┄ base case (8 hr by 2029)┄ ┄ bear case (20 min by 2029)hover a projection ↗
Dummy data until v1 measurement
Success threshold
Each chart below shows the task length where the model passes 50% of the time. 50% is the METR-standard horizon; higher = stricter.
§ II · Per-model deep dive

Where does today's best model break, family by family?

For each task family, success rate falls as the job gets longer. Where the curve crosses your chosen threshold (50%) is the horizon for that family. Pick another frontier model to see how horizons collapse as you move back in time.

Logistic fit over log task length. Confidence bands omitted in this view; see methodology §5 for the fit.

Model
Current frontier
0%25%50%75%100%1 sec10 sec1 min10 min1 hour1 day1 week1 mo50% success thresholdPass rateTask length (human-completion time, log)Customer service consistency12 hr · ServiceAmbient clinical scribing3 hr · ClinicalCBT-protocol delivery1 hr · Mental healthK-12 tutoring (one chapter)30 min · EducationCatching misaligned chatbot advice10 min · SafetyElder-care robot1 min · EmbodiedVisual cognition (one-shot)2 sec · Viscog
Dummy data until v1 measurement
§ III · Methodology

How long since the last mistake?

The quality of deployed assistants is the same one reliability engineers have asked of aircraft, power plants, and surgical tools for decades. Every deployed AI agent's goal is to run forever without errors. ARIA RUN measures how close they are.

Builds on METR's Time Horizon, adapted for ARIA's multi-domain task space and stakeholder-authored harm rubrics.

01
Assemble tasks
Tasks of varying length drawn from every ARIA (UK Advanced Research + Invention Agency) Work Package. Each carries a stakeholder-authored harm rubric and a human-completion-time measurement from trained professionals.
02
Run frontier models
Standardized harness, pass/fail per rubric, multiple trials per task. Deploy in the real world when simulation is insufficient.
03
Fit pass-rate curves
For each model, a curve of pass rate as a function of task length. The point where it crosses your chosen threshold (50%) is that model's horizon.
04
Track horizons over time
Plot horizons across frontier releases. Task-family curves reveal which capabilities are saturating, accelerating, or stuck.
§ IV · METR baseline

How METR derives a time horizon

For each frontier model, success rate falls as tasks get longer. Where the curve crosses 50% is that model's time horizon. METR (Model Evaluation and Threat Research, the AI-safety org that pioneered this measurement) found that the 50% horizon doubles roughly every six months.

We adopt this methodology wholesale, then extend it to settings METR doesn't cover: clinical encounters, classrooms, homes.

1s10s1m10m1h202320242025202650% success threshold · log scaleGPT-425 secGPT-4o1.2 minClaude Sonnet 3.52 minGPT-58.5 minClaude Opus 4.725 min
§ V · Task families over time

How long each frontier model can work on various ARIA tasks with ≥50% success

Curve shapes reflect task-specific progress. Seven pilot families — visual cognition anchors the “0-minute” end (the summer-camp focus); more agentic families in development with partner labs.

7 pilot families · 3 ship in v0.1
1s10s1m10m1h1d1w1mo2023202420252026202750% success horizon · log scaleCustomer service consistency~12 hr · ServiceAmbient clinical scribing~3 hr · ClinicalCBT-protocol delivery~1 hr · Mental healthK-12 tutoring (one chapter)~30 min · EducationCatching misaligned chatbot advice~10 min · SafetyElder-care robot~1 min · EmbodiedVisual cognition (one-shot)~2 sec · Viscog
Dummy data until v1 measurement
§ VI · Roadmap

Year 1 — what we build

A v0.1 scoreboard — three domains, five tasks each, four frontier models — shipped with the first ARIA RUN report.
Q1 – Q2
Foundation
  • Initial task taxonomy across 3 pilot domains
  • Harness v0 design — simulated-patient tier
  • Summer 2026 bootcamp + hackathon at Brown
Q3
First measurements
  • Harness v0 operational
  • First 4 frontier models scored on 15 tasks
  • Per-task 50% horizons computed with confidence bands
  • Frontier-lab communications
Q4
First public release
  • v0.1 scoreboard published at run.brown.edu
  • First ARIA RUN report
  • Policy briefs to state regulatory groups
  • Y2 task expansion plan
Featured · Summer 2026

Building a community-curated cognitive task benchmark for trustworthy AI

Format
~1-week bootcamp at Brown, then ~25% effort through a second-week hackathon.
Dates
TBD · bootcamp in-person at Brown, hackathon location TBD.
Team
~5 Brown students + ~5 PhD students / postdocs from ARIA partner labs (CS, cognitive science, clinical / mental health). Open participation from the broader ARIA community at the hackathon.
Mentor
Thomas Serre (Serre Lab, Brown).
Co-leads
Alekh Karkada Ashok · Sixuan Chen · Peisen Zhou.
Express interest →

AI systems deployed in mental and behavioral health (and elsewhere) are increasingly tested against benchmarks borrowed from coding, math, or general knowledge — domains where “trustworthy” reduces to “correct.” But the cognitive tasks that matter for human users — perspective taking, reasoning under uncertainty, metacognition, sensitivity to social and clinical context — are largely absent from public LLM evaluations, and the human-baseline data needed to interpret model performance on such tasks is scattered across labs in non-standard formats.

What we'll build
  1. Standardize existing cognitive tasks from ARIA partner labs into a shared open format with paired human data.
  2. Design new tasks in collaboration that probe AI reliability in real-world mental- and behavioral-health-relevant scenarios.
  3. Build a public web platform that runs LLMs via Brown CCV's LiteLLM API gateway and produces a live human-vs-model leaderboard.

The project is flexible and will be shaped by the interests of the students on the team — the benchmark, the platform, and the analyses are intended as a community resource that grows beyond the camp.

§ VII · Collaborate

ARIA RUN is still being shaped.

We're in the planning phase, and we're looking for collaborators at every level — students, clinicians, postdocs, engineers, and principal investigators — to help decide what we build, which tasks we measure, and what real-world reliability should mean.

Leave your email and we'll reach out as the project takes shape. One note per milestone — no more.

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Especially looking for
  • Brown students (CS, cog-sci, clinical)
  • ARIA partner-lab PhDs and postdocs
  • Clinicians and educators with deployed-AI experience
  • Principal investigators interested in co-authoring task families
  • Frontier-lab researchers willing to share compute