Explore and query data on S3, Cloudflare R2, GCS, MinIO, or any S3-compatible storage. Use when the user mentions an s3://, r2://, gs://, or gcs:// URL, asks "what's in this bucket", wants to list remote files, preview remote Parquet/CSV/JSON, or query data on object storage without downloading it.

You are helping the user explore data on remote object storage using DuckDB. URL: $0 Question: ${1: list and describe what's there} Step 1 — Detect provider and set up credentials Based on the URL or user context, prepend the appropriate secret configuration: Provider URL patterns Secret setup AWS S3 s3:// CREATE SECRET (TYPE S3, PROVIDER credential chain); Cloudflare R2 r2:// , s3:// with R2 endpoint CREATE SECRET (TYPE R2, PROVIDER credential chain); GCS gs:// , gcs:// CREATE SECRET (TYPE GCS, PROVIDER credential chain); MinIO / custom s3:// with custom endpoint CREATE SECRET (TYPE S3, KEY ID '...', SECRET '...', ENDPOINT '...', USE SSL true); For R2, if the user provides an account ID, the endpoint is <account id .r2.cloudflarestorage.com . R2 URLs like r2://bucket/path should be rewritten to s3://bucket/path with the R2 secret. For public buckets (e.g., Overture Maps, AWS open data), no secret is needed — skip this step. Always prepend: Step 2 — Determine what the URL points to If the URL looks like a directory or bucket (no file extension, or ends with / ), list its contents with sizes: Note: only select filename , size , last modified — never select content , which would download the actual files. If the URL points to a specific file or glob pattern (has a file extension or contains ), preview it: For Parquet files , get row counts and sizes from metadata (no data download): Step 3 — Answer the question Using the listing, schema, or sample data, answer: ${1: list and describe what's there} If the user asks an analytical question (e.g., "how many rows match X"), write and run the appropriate SQL query. DuckDB pushes predicates down into Parquet on S3, so filtering is efficient even on large remote datasets. Error handling duckdb: command not found → delegate to /duckdb skills:install duckdb Access denied / 403 → suggest the user check credentials: aws configure , environment variables, or provide explicit key/secret Bucket not found / 404 → check the URL and region Timeout on large listing → suggest narrowing the glob pattern or adding a prefix

s3-explore