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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds two things annotations cannot: the data basis ('aggregate snapshot counts', i.e. pre-aggregated not live per-record data) and an entitlement gate ('VIP required'), both of which affect whether and how an agent should call it.

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?

Two sentences, zero filler, with the core operation and cardinality front-loaded and the access constraint appended. Nothing repeats the tool name verbatim.

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 should say what a comparison yields (per-pathway aggregate counts, a table, etc.) — 'using aggregate snapshot counts' only hints at it. The untouched month parameter and unstated code formats leave meaningful gaps for a tool with 0% schema coverage.

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 0%, so the description carries the burden. It does convey the pathway array's shape (visa/state pairs, 2-5 items) and that a single occupation is required, but the optional 'month' parameter is never mentioned, nor are the expected formats (6-digit occupation code, MM/YYYY month, short visa/state codes).

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 (compare) and resource (visa/state pathways), plus cardinality (two to five) and scope (one occupation). This implicitly separates it from compare_occupations, though it never names that sibling explicitly.

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?

Gives clear selection context: exactly one occupation, 2-5 pathways, and a hard prerequisite ('VIP required') that an agent must check before calling. It stops short of naming alternatives such as get_pathway_overview for single-pathway inspection or compare_occupations for cross-occupation comparison.

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