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

The annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false. The description adds useful context beyond that: it returns the 'full public record' and the data source is 'as published by IP Australia', which tells the agent about completeness and authority. It does not discuss missing or invalid application numbers, so it is not exhaustive.

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 definition is a single front-loaded sentence with no filler. Every phrase contributes: the action, the scope, the identifier type, and the data source.

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 simple one-parameter lookup with full schema coverage, clear annotations, and an output schema, the description provides enough to invoke it correctly: it names the identifier, the record scope, and the publishing authority. Return-value details are appropriately left to the output schema.

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%, and the single 'number' parameter is already documented with an example. The description only restates that lookup is 'by application number', adding no syntax or format detail beyond the schema, so the baseline 3 applies.

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 resource ('full public record of one Australian patent'), and scopes it to lookup 'by application number'. This clearly distinguishes it from the sibling search tool au_search_patents, which would be used for discovery rather than retrieving one known patent.

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 'by application number' implies the caller must already know the application number, but the description never explicitly says when to use this versus au_search_patents or what to do if only a name/query is available. Usage is inferable but not stated with alternatives or exclusions.

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