calculate_delivery_zone_and_fee

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

With no annotations provided, the description carries the burden of behavioral disclosure. It reveals that the tool invokes the Google Maps Platform Routes API, computes road distance rather than straight-line distance, and returns zone, fee, hours, and COD fee. This is good transparency for a non-mutating calculation tool, though it does not mention failure behavior or API rate implications.

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?

A single dense sentence conveys the main action, inputs' purpose, fee structure, and return values with no filler. The key information is front-loaded in the verb and resource.

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?

Given there is no output schema, the description compensates by explicitly listing the expected return values: distance, zone classification, fees, estimated hours, and COD fee. It also identifies the external API. Minor gaps remain, such as how invalid addresses are handled, but the tool is simple enough that the description is largely sufficient.

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 schema already documents all three parameters. The description adds useful context about outputs and fee tiers, but it does not elaborate on parameter meanings beyond the schema, so the baseline score applies.

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 action (compute, classify, return) on a clear resource: delivery zone and fee for Bangladesh. It also enumerates concrete outputs (distance, zone tiers with fees, delivery hours, COD fee), which distinguishes it from sibling tools like 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 description clearly implies the tool is for computing delivery zone and fee, but it does not explicitly state when to prefer it over alternatives such as compare_courier_rates or validate_and_geocode_address. Usage context is inferable but not directly stated.

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