gcs_list_objectsList objects in a Google Cloud Storage bucket and filter by prefix to inspect folder-like paths or locate files.
Lists objects in a bucket, optionally filtered by prefix (folder-like path).
| Name | Required | Description | Default |
|---|---|---|---|
| bucket | Yes | Bucket name (without gs:// prefix) | |
| prefix | No | ||
| delimiter | No | Set to "/" to emulate folder listing | |
| pageToken | No |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, yet it says nothing about pagination (despite a pageToken parameter), result limits, ordering, or return shape. The prefix-as-folder-path note is helpful but leaves the agent guessing on result-set size and iteration.
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 well-formed sentence with the core operation front-loaded and no wasted words. It is efficient, though the terseness is also the source of the missing behavioral detail.
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?
No output schema, no annotations, 4 parameters at 50% coverage, and nothing about pagination or result size — the most important missing context for a list tool. The definition is under-specified for an agent that must page through results.
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 coverage is 50%: bucket and delimiter are documented in the schema while prefix and pageToken are not. The description compensates for prefix by explaining its folder-like path semantics, but leaves pageToken and delimiter behavior to the schema, so it adds only partial value.
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+resource (lists objects) and scopes it to a bucket, which cleanly separates it from siblings like gcs_list_buckets and gcs_get_object_metadata. It doesn't explicitly name the alternative tools, but the operation is unambiguous.
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?
No guidance on when to use this versus gcs_list_buckets, gcs_get_object_metadata, or gcs_download_object, and no stated preconditions (e.g., required permissions, bucket existence). The 'optionally filtered by prefix' note is the only contextual hint.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.