Agent4CT is a continuously-running LLM agent that improves a CT reconstruction codebase by editing it, running short experiments on a Slurm GPU cluster, and keeping or discarding changes based on the resulting metrics. The pattern is borrowed from karpathy/autoresearch and generalised to five CT-imaging benchmarks — the Pentathlon.

Live · The dashboard at dashboard.html shows every run, every iteration, and the agents' shared scratch pad — including the side-by-side reconstruction images for each iteration.
Active rebuild · The Mayo-LDCT leaderboard (real helical data, Wagner split) is being rebuilt from scratch on the LME cluster — 19 solvers driven to the iter-20 hard stop. Per-dataset progress (Mayo-LDCT, Breast-CT, Demo-DL) is on the dashboard.

The Pentathlon

Five public AAPM CT reconstruction challenges, run on the same recon backbone (PYRO-NN fan-beam, Wagner / Siemens-AS geometry):

Mayo LDCT

AAPM Low Dose CT Grand Challenge (2016) — abdomen / chest / head, 25 % low-dose.

Metric: PSNR + SSIM vs high-dose recon

DL-Sparse-View CT

2021 — 2D breast phantom, 128-view sparse fan-beam, perfectly-known truth.

Metric: RMSE vs exact phantom

TrueCT

Truth-based CT (2022) — 200 virtual patients, mono-energetic phantom truth.

Metric: PSNR + RMSE vs mono-energetic truth

CT-MAR

CT Metal Artifact Reduction (2024) — sinogram + image pairs, 8-metric IQ score.

Metric: aggregate clinical IQ

DL-Spectral CT

Spectral CT (2022) — 1000 cases, two kVp, three-tissue map decomposition.

Metric: tissue-map RMSE

See Pentathlon for the headroom-recovered scoring and per-challenge train/val/test splits.

How the loop runs

Each iteration is one 5-minute Slurm job. The agent edits pentathlon/<challenge>/solver.py, the harness runs the job, computes the validation metric, and decides keep / discard via git. Every 30 iterations a 1-hour stage job runs on a 3× larger subset to catch overfitting. Test sets are touched exactly once, at the end. See Agents.

🏆 Leaderboards

Best-of-best per solver per dataset under the canonical calibrated-SSIM-headroom scoring convention.

The champion per dataset (single canonical ranking = headroom, SSIM tiebreak) is rendered live from the registry below, so it never drifts from the dataset boards.

loading champions…

See Leaderboards for the full per-solver rankings (every solver, below-baseline dimmed, with comparison images) and the cross-dataset summary.