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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new operational context — 'Free to call; does not consume account balance' — which an agent needs when choosing between candidate calls. It does not describe pagination or default page size behavior, though the schema covers limit.

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?

Three short sentences, front-loaded with the resource and the reason for calling, with the cost note last. No filler and nothing that restates the tool name.

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?

There is no output schema, so the description usefully sketches the return shape (groups plus their IDs) and gives an example. It does not mention that results may be large or paginated via limit, but for a simple free lookup this is nearly complete.

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%, with both limit and search fully documented in the schema, so the baseline is 3. The description adds no filter syntax, matching rules, or search behavior beyond what the schema already states.

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 (List) and resource (high-level industry groups) and explains what the returned IDs are for ('use in industryGroupIds filters'), with a concrete example value. The implicit contrast with the finer-grained list_industries sibling is present via 'high-level' but never made explicit.

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 a clear condition: 'Use when broad sector filtering is needed.' That tells the agent when this tool fits, but it does not name the alternative (list_industries) or state when to prefer that one instead, so the routing decision is left partly to inference.

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