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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds some useful provenance context — invitations figures are 'estimated' and the cutoff projection is a 'frozen forecast' — but says nothing about freshness, refresh cadence, or failure behavior for unrecognized ANZSCO codes.

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?

A single front-loaded sentence naming the subject first, then the returned fields. It is dense but every clause corresponds to a distinct data point, with no filler; the long comma-list is the only mild structural weakness.

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 carries the return-shape burden and does so well, naming each field an agent will receive. Read-only annotations cover the safety side, so the only gap is operational (data freshness/staleness and error cases) rather than something needed to call the tool correctly.

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 parameters are fully documented in the schema (the occupation ANZSCO/URL format and the locale enum). The description only restates the 'one ANZSCO occupation' scope and adds no form error handling or locale nuance 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?

States a specific verb and resource: invitation round history for Subclass 189 (and 491 family sponsored) scoped to a single ANZSCO occupation, then enumerates the exact data returned. It is far more specific than a tautology, but it never distinguishes itself from the close sibling estimate_189_invitation, so it falls short of a 5.

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 implies its use by enumerating historical round data (dates, invited/not, cutoffs) and a frozen forecast, but it never states when to prefer this over estimate_189_invitation or any other sibling, nor any prerequisites. Usage is inferable from the name/content rather than stated.

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