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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds an authorization requirement ('apiKey'), which is useful extra context, but says nothing about return volume, pagination, or ordering.

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 short sentences, front-loaded with the action and resource, with no filler. The only slight noise is the apiKey mention, which does not correspond to a declared parameter and could momentarily mislead.

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 single-parameter, read-only listing tool with rich annotations and no output schema, the description covers action, resource, scope, and auth. Return values need not be explained given no output schema, though pagination behavior would have been a nice addition.

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% and there is only one parameter, so the schema already documents farmId as 'The unique farm ID'. The description restates that farmId is required but adds no format or sourcing detail beyond the schema — baseline 3.

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 ('Retrieve registered farm vehicles') and scopes it to mileage logging, which links it to siblings like log_mileage and get_mileage_logs. It stops short of explicitly distinguishing itself from those siblings, so it's clear but not fully differentiated.

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?

'For mileage logging' implies the usage context, so an agent can infer this is a prerequisite lookup before logging mileage. However, it names no alternatives and gives no explicit when-to-use/when-not guidance relative to get_mileage_logs or log_mileage.

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