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

Annotations already mark the tool read-only, idempotent, and non-destructive, and the description adds the key behavioral nuance that results are estimates/screening-level ('Estimate', 'indicative') rather than definitive answers. It also clarifies the tool is not advice, which is a meaningful behavioral boundary beyond the annotations.

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?

The description is two sentences with no filler: the first front-loads the full set of outputs, and the second adds the essential screening/not-advice caveat. Every clause contributes information.

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?

For a read-only estimation tool with a present output schema and complete parameter documentation, the description provides enough context to invoke it correctly. The only minor gap is that it does not hint at data-source assumptions or accuracy expectations, though 'indicative' partially covers this.

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?

All five parameters are fully documented in the schema (100% coverage), so the description carries no obligation to explain parameter meaning. It does reinforce that inputs are coordinates of a commercial building and that incentives are Australian/state-specific, but it adds no semantic detail beyond the 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?

The description opens with 'Estimate' and enumerates the concrete outputs (mapped roof area, capacity, generation, energy value, incentives) plus the target input ('coordinates of a commercial building'), so an agent knows exactly what the tool does even without opening the schema. There are no siblings to differentiate, but the scope is specific enough to stand alone.

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?

The 'Screening only; not engineering, financial, or eligibility advice' clause explicitly bounds when the tool should be used and when it should not be relied upon. With no sibling tools, explicit alternative routing is impossible, but the screening vs. advice distinction gives practical decision guidance.

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