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

Annotations already cover the safety profile (readOnlyHint, destructiveHint=false, openWorldHint=false), and the description adds genuine context beyond them: nothing is launched and therefore no EF is consumed, plus the EF unit of measure. It does not disclose auth requirements or whether the estimate is binding.

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?

Two sentences, front-loaded with the action and scope, followed by the one piece of unit information needed to interpret the result. No filler or repetition of the title.

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?

Although there is no output schema, the description names what the call returns (cost in EF and volume), which is the key unknown for a 5-parameter estimation tool. The only real gap is the unexplained scrap_mode enum, which affects the accuracy of the estimate.

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 80%, so the schema already explains queries, zones, country and stop_at; baseline is 3. The description adds no parameter-level guidance, and the one enum (scrap_mode: fast/normal/ultra) has neither a schema description nor any explanation in the description.

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 and resource ('Estimate the cost (EF) and volume of a Google Maps extraction') and explicitly carves out the scope with 'WITHOUT launching it', which separates it from create_scrap_job. The EF unit definition further pins down what 'cost' means in this domain.

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 phrase 'WITHOUT launching it' makes the pre-flight use case clear: call this before spending quota on a real extraction. It does not name create_scrap_job as the alternative or state explicit exclusions, so it falls short of a full when/when-not rule.

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