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

Annotations already cover read-only, idempotent, open-world and non-destructive semantics, so the bar is low; the description still adds real context by stating this is a public endpoint (no auth), that results are English natural-language text, and that sources/conditions/pagination are preserved. The pagination and 'preserving sources' phrasing is vague and unexplained, keeping it short of a 5.

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 front-loaded with the tool's identity and scope, then the use case, then output characteristics — a sound order with no repeated content. The first sentence is a long field laundry list, and 'preserving sources, conditions and pagination' is loose phrasing, but nothing is outright 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?

With no output schema, the description fully carries the burden of describing returns, and it does so comprehensively: identity fields, registration status/period, regulator, head office, all regulatory decisions with status/dates/review, and linked CRICOS schools with course counts. The only shortfall is that pagination behavior for decision lists is asserted rather than explained.

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 the schema already documents the accepted code/URL forms, the locale enum and the includeDecisionText toggle. The description only indirectly hints at the includeDecisionText effect via 'the original decision text' and adds no format or boundary detail beyond the schema — 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 opens with a specific verb+resource ('One Australian Registered Training Organisation (RTO) by RTO code') and then enumerates the exact fields returned, so the scope is unmistakable. It never names its closest siblings (search_rtos, get_rto_regulatory_actions), whose overlap with 'every regulatory decision' and with RTO retrieval is left for the agent to infer.

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?

'Use it to check whether a vocational provider is registered and in good standing' gives a clear intended use, which is better than nothing. But there is no routing guidance against search_rtos when the code is unknown, nor against get_rto_regulatory_actions even though this tool claims to return every regulatory decision — the agent is left to guess which to call.

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