get_account_usage

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

Annotations already indicate readOnlyHint: true, and the description reinforces this with 'Get'. More importantly, it adds behavioral context by specifying the exact categories of usage (e.g., keyword inspections, autocomplete queries) and that it reflects 'used vs. allowed' for the 'current billing period'. No contradictions; the description enriches beyond the annotation.

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?

The description is a single, well-structured sentence that front-loads the core purpose ('Get current account usage and plan limits') and efficiently lists the covered categories with a colon and commas. No verbosity, perfect length for the complexity.

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?

Given the absence of parameters and output schema, the description provides a solid overview of the expected return data (usage counts for six categories plus API requests, with 'used vs. allowed' limits). It does not explicitly state the response format, but for a zero-param read-only endpoint, the coverage is thorough enough for an agent to understand 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?

The tool accepts zero parameters, so the description is not required to elaborate on any parameter semantics. Per the rubric, a baseline of 4 applies to zero-parameter tools. The description does not need to compensate for schema gaps because there are no parameters.

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 uses a specific verb ('Get') and clearly identifies the resource ('current account usage and plan limits'), then enumerates the exact data categories (applications, keywords, competitors, etc.) and temporal scope ('current billing period'). This makes the tool's purpose immediately clear and distinguishes it from sibling list_* 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 clearly implies 'use this when you need usage/limit info' and indirectly differentiates from siblings like list_applications (which return actual records), but it does not explicitly mention alternatives or state when not to use it. The context is clear; explicit exclusions are missing.

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