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

Annotations already declare readOnlyHint=true and destructively=false, so the safety profile is covered. The description adds behavioral value by specifying the content of the response (permissions, limits, policy, suspension state) and notes the tool is 'Free' – a cost-related trait not present in annotations. This goes beyond mere repetition of structured fields.

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 sentences, with the core action front-loaded and the data list compactly delivered. The list is long but each item is a distinct useful piece of information; 'Free.' is a separate short sentence for emphasis. It remains efficient and readable.

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, output-schema-less tool, the description sufficiently explains what the response contains (identity and permissions, limits, policy, suspension state). It does not detail the exact response structure, but the absence of an output schema makes that less critical; the agent has enough to know what to expect.

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?

There are zero parameters, and the schema is an empty object. With no parameters to document, the baseline is 4; the description adds no parameter information, but none 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 states a specific verb-resource pair ('Returns this key's identity and permissions') and enumerates the exact data categories returned. This clearly distinguishes it from siblings like get_usage (usage metrics) or get_operation (operation status), so an agent can select it confidently.

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: an agent needing scopes, spend caps, or capacity limits should call this tool. However, it provides no explicit 'use this when' guidance, no exclusions, and no alternative tool names for other purposes, leaving the agent to infer the tool's role among siblings.

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