279,196 image alt-text pairs from 489 Bluesky accounts, collected via the public AT Protocol APIs. Every account validated at 90%+ alt-text rate with substantive descriptions. One row per image, not per post.
Includes a 125K-row firehose sample (14.5 hours of live network traffic) for contrastive analysis.
Collection period: April 2026
Total rows: 279,196 (corpus) + 125,645 (firehose) = 404,841… See the full description on the dataset page:
https://huggingface.co/datasets/lukeslp/bluesky-alt-text.
