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

Annotations already cover read-only, idempotent, closed-world safety, so the description's value is in the data shape: values only, mesh-block granularity, includes suburb totals, and a pointer to where polygons live. That is meaningful context beyond the annotations, but it doesn't describe result format or how totals relate to block rows.

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 with the report context front-loaded and the geometry caveat last. The opening clause 'Shown in the suburb report as...' is mildly presentation-oriented padding but still routes the agent.

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?

No output schema exists, and the description does state what the response contains (per-block residents and dwellings plus suburb totals) and that it carries no geometry. Missing only the identifier semantics for suburb_name, which is the one real gap for a correct call.

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?

One parameter with 0% schema description coverage, and the description only implies it selects 'the suburb' without stating whether it is a name, code, or slug, or what happens on ambiguity. It adds a little scope meaning but does not compensate for the empty schema.

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 the resource (residents and dwellings per mesh block plus suburb totals) and its role as the Demographics 'Population' map layer. It is clearly distinguished from the geometry sibling by explicitly saying polygons come from /shapes/mesh-blocks, though it never names the closest data siblings (suburbs_demographics_all, population_history).

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?

Implies usage by placing it in the suburb report's Demographics section and by pointing to the companion shapes endpoint for geometry. It does not say when to pick this over suburbs_demographics_all or suburbs_demographics_population_history, nor any prerequisites.

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