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 real value by disclosing the shape of the result (daily counts plus top cities/zips) and a 'Free' pricing tier, but says nothing about result limits, how many cities/zips are returned, or behavior when days exceeds the 90-day cap.

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 covering outputs, scope, and window, with no padding. The trailing 'Free.' fragment is terse but does convey a genuine constraint, so it earns its place.

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?

This is a simple 3-parameter read tool with no output schema, so the description should fully describe what comes back and how jurisdiction interacts with the result. It covers the return shape adequately but leaves the jurisdiction filter and result-size behavior undocumented, which is a clear gap for a geo-breakdown tool.

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 67%, so the baseline is 3. The description reinforces 'one category' and 'last N days', but omits the jurisdiction parameter entirely, which is a 30-value enum and the main narrowing knob; the schema alone has to carry that ('Use list_coverage for names').

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 names the concrete outputs (daily permit counts, busiest cities and zip codes) and the scoping dimensions (one category, last N days), which is clearer than a bare 'get trends'. It does not, however, contrast itself with siblings like permit_stats, count_permits, or weekly_permit_report, so an agent still has to infer the boundary.

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?

There is no explicit when-to-use or when-not-to-use guidance and no named alternative among the six siblings. The phrase 'over the last N days' only weakly implies time-series/trend use versus point-in-time counts, leaving the choice between this and permit_stats largely to guesswork.

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