List storage buckets, or list objects in a specific bucket with optional prefix filter.
| Name | Required | Description | Default |
|---|---|---|---|
| name | No | Alias of bucket — accepted for symmetry with create/delete | |
| bucket | No | Bucket name (aliases: name). If omitted, lists all buckets. | |
| prefix | No | Filter objects by key prefix |
Changes observed during successful MCP inspections.
Input schema / properties / bucket / descriptionPrevious value: -"Bucket name. If omitted, lists all buckets."New value: +"Bucket name (aliases: name). If omitted, lists all buckets."Input schema / properties / nameAdded value: +{
+ "description": "Alias of bucket — accepted for symmetry with create/delete",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds the dual listing mode and prefix filtering, but says nothing about pagination, result limits, or return shape for a list operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single efficient sentence that front-loads the primary mode (list buckets) before the conditional secondary mode. No wasted words, though it is terse enough to leave the mode-switch rule implicit.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only list tool with full annotation coverage and 100% schema documentation, the description covers the essential behavior. No output schema exists, but the missing pagination/return-format detail is a minor gap for a listing tool.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents all three parameters including the name/bucket alias relationship. The description merely restates the bucket and prefix roles without adding syntax, format, or behavioral detail beyond the schema, so baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb ('List') and resource ('storage buckets', 'objects in a specific bucket'), and the dual-mode behavior is clear. It reads distinctly from the write/transfer siblings (create_bucket, delete_object, upload, download), though it does not name any sibling explicitly.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Usage is only implied: omitting the bucket lists all buckets, and supplying one lists objects with an optional prefix. There is no explicit when-to-use/when-not guidance or pointer to alternatives such as scalix_storage_download for retrieving a specific object.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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