Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It discloses the primary output (list of people, sharing links, permission IDs) but does not state whether the operation is read-only, any authorization requirements, or potential side effects. Since it is a listing operation, the read-only nature is implied but not explicit. It also does not mention pagination or error behavior.

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, tightly worded sentence that front-loads the core action ('List everyone with access to an item') and then adds the key output details (sharing links, permissionId). There is no filler or repetition.

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?

The tool is simple (2 required params, no output schema) but the description does not explain itemId or explicitly state read-only behavior. Given no annotations, the description should at least clarify the parameters and side effects. It provides the core output but leaves the agent to infer how to supply itemId and whether it is safe to call.

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%: mailbox has a description, but itemId has none. The description does not clarify what 'item' refers to or how to obtain itemId, leaving it under-specified. The description adds no parameter information beyond the schema, failing to compensate for the missing itemId documentation.

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?

The description clearly states the tool lists everyone with access to an item, includes sharing links, and provides the permissionId needed for revocation. It uses a specific verb ('List') and resource ('everyone with access to an item'), and the mention of permissionId for revocation distinguishes it from plain listing tools.

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?

The description implies usage (to see who has access and prepare for revocation) but does not explicitly state when to use it versus alternatives like list_gdrive_permissions or share/unshare tools. No exclusions are given, but the context is clear from the name. However, explicit guidance on when to choose this tool is absent.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.