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

The annotations already declare readOnlyHint=true and openWorldHint=false, so the description's remaining job is lighter. It adds useful context by stating that results include current and legacy rule periods with official Home Affairs sources, which tells the agent what kind of information to expect without contradicting 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, front-loaded with the primary purpose and then the return behavior. Every phrase adds useful information, with no repetition or filler.

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 that the tool has no parameters and no output schema, the description is complete enough for an agent to understand what the tool does and what it returns. It specifies the English categories, visa type, rule periods, and source authority without needing additional structured fields.

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 takes no parameters, so there are no parameter semantics to explain. The baseline for zero parameters is 4, and the description does not need to add parameter details because none exist.

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 ('Look up') and names the exact resource and scope: PTE Academic score thresholds for Australian Competent, Proficient and Superior English, plus Temporary Graduate visa 485 component minimums. This clearly differentiates it from the sibling tools, which cover test format, question types, and question search.

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 for when the tool is appropriate: looking up Australian PTE score requirements. It does not explicitly state when not to use it or name alternatives, but the specialized scope makes the intended use obvious relative to the generic sibling tools.

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