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

With empty annotations, the description bears full burden for behavioral disclosure. It only mentions authentication, omitting details like rate limits, data scope (e.g., current period or cumulative), or error conditions (e.g., unauthorized access).

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, no redundancy. Every part serves a purpose: identifying the function and providing auth instructions. Front-loaded with the essential purpose.

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 description covers basic function and authentication, but lacks detail on what the usage statistics contain (e.g., request counts, quotas) and output format. Since there is no output schema, more detail would be helpful for an agent to interpret 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?

The input schema has zero parameters and 100% coverage, so the baseline is 4. The description adds no parameter info but includes authentication guidance, which is relevant context. No further elaboration 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 clearly states the tool retrieves API usage statistics for the authenticated agent, using a specific verb 'Get' and a well-defined resource. It distinguishes from siblings like get-wallet and get-wallet-transactions by focusing on usage data.

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 gives clear context by indicating authentication is required and how to provide credentials ('Pass API key via X-Agent-Key header or Authorization: Bearer'). It does not explicitly mention when to use alternative tools, but the purpose is straightforward.

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