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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds a useful scoping fact — results are limited to the linked Market Brew account — which is genuine behavioral context. It does not disclose what a 'report definition' contains 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?

Two short sentences, front-loaded and free of filler. It is appropriately sized; the brevity is fine given the low 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?

A read-only lookup with one required param and no output schema needs to at least identify the id's meaning and what a report definition is. The account-scoping note helps, but the id semantics gap and tautological purpose keep it at minimum viable.

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 is a single required 'id' parameter with 0% schema description coverage, so the description must compensate. It says nothing about what the id refers to (definition id? report id?) or accepted format, leaving significant ambiguity.

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 restates the title almost verbatim ('get a usage report definition'), which is tautological rather than clarifying. It does not name the resource scope or distinguish it from siblings like get_usage_metrics, get_usage_metric_history, or list_usage_reports.

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 phrase 'Use this when the user asks to get a usage report definition' is a tautology of the name and offers no real routing guidance. Notably, it fails to distinguish this from list_usage_reports or the usage metric siblings.

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