Why are steps missing from a CSV metric export?

Export limits can prevent the entire run history from being exported as a CSV or using the run.history API. To access the complete run history, download the run history artifact using Parquet format:

import wandb
import pandas as pd

run = wandb.init()
artifact = run.use_artifact('<entity>/<project>/<run-id>-history:v0', type='wandb-history')
artifact_dir = artifact.download()
df = pd.read_parquet('<path to .parquet file>')