Lists every bucket in the configured Backblaze B2 account, as JSON objects with bucketId, bucketName, and bucketType.

Lists one page of current files in a bucket, as JSON objects with fileName, fileId, contentLength, contentType, and uploadedAt. Optionally filtered by name prefix. The result reports truncated and nextFileName when more files exist beyond the page.

Uploads a file from the local filesystem into a bucket and returns the stored file id, name, size, and type. The local path must sit inside the directory named by B2_UPLOAD_ROOT; uploads are refused otherwise. Uploading an existing name adds a new version rather than replacing the old one.

Downloads a file from a bucket to the local filesystem and returns where it landed, its size, type, and SHA-1. The destination must sit inside the directory named by B2_DOWNLOAD_ROOT. An existing file is not replaced unless overwrite is true. File content is never returned, only the path it was written to.

Hides a file so it stops appearing in b2_list_files. Reversible: the data stays in version history and b2_unhide_file restores it. Prefer this over deleting when the goal is to remove something from view.

Removes the latest hide marker, making a hidden file visible again. If the file was not hidden, this reports restored false rather than failing.

PERMANENTLY destroys ONE version of a file. B2 cannot undo this, and older versions of the same name are left in place. Requires the exact fileId, which you must get from b2_list_files first: this tool will not look one up from a file name. Refused unless B2_AUDIT_LOG is configured, since every deletion is recorded. When B2_ARCHIVE_ROOT is set, a copy of the version is saved locally before it is destroyed. To remove a file from view reversibly, use b2_hide_file instead.

Reports bytes stored per bucket and how that compares to a budget, flagging buckets over the threshold. B2 exposes no usage endpoint, so this is computed by summing every file version, INCLUDING old versions, which B2 also bills for. The figure EXCLUDES parts of unfinished large uploads, which B2 does bill for; those uploads are counted separately as unfinishedLargeFiles, so treat bytesUsed as a floor rather than a total. Omitting bucketName scans every bucket, which costs one transaction per 1000 versions per bucket and is the most expensive call this server makes. A scan is capped at 20 pages per bucket and sets truncated when the cap stops it.

Lists the application keys on the account with their capabilities, bucket restrictions, name prefix, and expiry. Contains NO key secrets: B2 returns a secret only when a key is created, and this server never creates keys. It does reveal what each key is permitted to do. Requires a key carrying the listKeys capability; a key scoped only to file operations will be told so.