calculate_delivery_zone_and_fee

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

With no annotations, the description carries the full behavioral burden. It does disclose an external dependency (Google Maps Routes API) and lists calculated outputs, but it does not clarify read-only behavior, side effects, failure modes, rate limits, or authentication needs.

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 definition is a single front-loaded sentence that lists the core calculation and the included outputs. The parenthetical fee examples are useful and every clause contributes to understanding the tool.

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 or annotations exist, so the description must carry more weight. It names the computed values but does not explain response structure, units for road distance, SLA format, or how the COD percentage is determined, leaving some gaps for an agent interpreting results.

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 100%, so the input schema already documents all three parameters. The description confirms the calculation applies to a single delivery address but adds no further parameter-level meaning or formatting guidance 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 states a specific verb (calculate) and concrete outputs: delivery zone, fee, road distance, SLA, and COD percentage. It is clear what the tool does, but it does not explicitly distinguish itself from siblings such as compare_courier_rates or validate_and_geocode_address.

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 'for a single delivery address' implies the intended scenario, and the tool appears useful for quoting a specific delivery. However, it does not state when to use this instead of sibling tools like compare_courier_rates, nor does it describe exclusions or prerequisites.

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