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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds meaningful context beyond those annotations by specifying that it inspects the current API key and reports scopes, which directly supports permission debugging.

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?

Two short sentences with no filler: the first front-loads the action and output fields, and the second states the purpose. Every sentence earns its place, and it avoids restating schema or annotation information.

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 parameterless tool with annotations covering side-effect safety, this description provides everything an agent needs to select and invoke it correctly: the resource, the returned fields, and the intended use case. The absence of an output schema is mitigated because the main return fields are explicitly listed.

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?

The tool accepts zero parameters and the input schema is empty, so there are no parameter semantics for the description to clarify. The baseline of 4 applies because no parameter documentation is needed.

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 names a specific verb ('Returns information') for a precise resource ('the current API key') and enumerates the returned fields: workspace name, available scopes, and key prefix. This clearly differentiates it from the many get_workspace/get_account sibling tools, which target broader workspace/account data rather than the API key context.

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?

'Useful for debugging permission issues' gives a clear, actionable context for when an agent should invoke this tool. It does not explicitly name alternative tools or state when not to use it, but for a zero-parameter whoami utility this is sufficient.

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