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

Annotations already declare readOnly/openWorld/idempotent/non-destructive, so the bar is lower, yet the description still adds real behavior: addresses are validated against the named municipality and ambiguous ones are refused with suggestions, and supplying a category conditionally adds market size, competitors and an opportunity score. These conditional-output and failure-mode details are exactly what the agent cannot infer from the structured fields.

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?

Roughly three sentences, front-loaded with the verb 'Profile the area', followed by conditional capability, use cases, then a caveat about address validation. Dense but every clause carries information; only the interleaved example quotes make it slightly harder to scan.

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 an output schema present and annotations covering the safety profile, the remaining burden is purpose, input intent, conditionality and failure handling — all covered. An agent can decide to call this tool and predict the refusal path for ambiguous addresses without opening the schema.

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 coverage is 100%, so the baseline is 3, and the description adds meaning on top: it frames radius_m versus walk_minutes as mutually exclusive ways to define the area ('instead of a circle') and ties category to the extra outputs it unlocks. It stops short of example syntax for coordinates or walk times, which the schema already handles.

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 precise verb+resource: profile the population, households, income, age and mapped businesses within a radius or walk time of an address, with market size and an opportunity score when a category is given. That scope is clearly distinct from point-topic siblings like income or crime, but the description never names an alternative tool (e.g. compare_areas or demographics), so the differential is left implicit.

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?

Offers concrete trigger scenarios ('who lives within 800 m of this shop', 'is there room for a bakery near Calle X') that make the intended use easy to recognize. It does not say when to prefer a sibling such as market_size or demographics, nor when this tool is the wrong choice, so it stops short of full routing guidance.

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