list_objects

List one folder level of a cloud object store by URL: Amazon S3 (and S3-compatible providers), Azure Blob Storage, or Google Cloud Storage. Read-only analytics (stays available under --mcp-read-only).

When to use

• "What files are in s3://reports/2026/?"
• Browse a bucket before opening a file with read_table.

Input schema

Parameter	Type	Required?	Default	Description
url	string	yes	(no default)	s3://bucket/prefix, az://container/prefix, or gs://bucket/prefix (empty prefix = bucket root)

Credentials

The MCP/CLI server authenticates with ambient credentials:

• S3: AWS_* environment variables or a cached SSO session.
• Azure: an Azure CLI login, plus AZURE_STORAGE_ACCOUNT (an az:// URL cannot carry the storage account name).
• GCS: Google application-default credentials, or GOOGLE_* environment variables.

The in-app assistant additionally uses your saved cloud connections (Settings > Cloud storage), so it can reach buckets configured with static keys or per-connection sign-in.

Response shape

{
  "url": "s3://reports/2026/",
  "count": 2,
  "objects": [
    { "name": "q1", "key": "2026/q1/", "url": "s3://reports/2026/q1/", "is_folder": true, "size": null, "modified": null },
    { "name": "summary.parquet", "key": "2026/summary.parquet", "url": "s3://reports/2026/summary.parquet", "is_folder": false, "size": 81234, "modified": "2026-06-20T11:02:00+00:00" }
  ]
}

Open a listed file by passing its url as the path of any read tool.

Example call

{
  "name": "list_objects",
  "arguments": {
    "url": "s3://reports/2026/"
  }
}

See also

• read_table: open a listed file (pass its url as path).
• grep_files: grep across local files in a directory.