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 safe read-only nature is covered. The description adds meaningful behavioral scope by specifying that it covers Iranian limitation periods across prosecution, execution, and filing deadlines, which is useful context beyond the annotations.

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 two sentences long, front-loads the core function, and contains no filler. The usage trigger is placed in the second sentence without redundancy.

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 two-parameter lookup tool with one required enum field and read-only annotations, the description covers the essential context: what is checked, which deadlines, and when to invoke it. It does not describe return format, but no output schema exists and this omission is acceptable given the tool's simplicity.

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?

Schema description coverage is 100%, so both case_category and crime_grade are already documented in the schema. The description restates the idea of a case category but adds no new semantic detail about the parameters, such as how crime_grade interacts with the criminal category.

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 ('Check'), a clear resource ('Iranian limitation periods'), and the three deadline types covered (prosecution, execution, filing). It also ties the tool to case categories, making its function distinct from the calculator siblings and lookup_law_article.

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 explicitly tells the agent when to use the tool: when the user asks whether a claim is time-barred or how long they have to file. It does not explicitly name alternatives or list when not to use it, but the trigger conditions are concrete and actionable.

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