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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description usefully adds a real behavioral trait beyond annotations: birth date and driver-licence data are never returned, which tells the agent what to expect in the response.

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?

Three terse fragments, front-loaded with the resource identity and followed by the key data limitation and the underlying endpoint. No filler, though the endpoint path is only marginally useful to an agent.

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?

A read-only single-resource lookup with one fully documented parameter and no output schema. The description covers the resource, the notable field exclusions, and the call target, leaving little ambiguity for invocation.

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?

There is one parameter with 100% schema description coverage, so the schema already carries the parameter documentation. The description adds nothing about the contact_id format beyond what the schema shows, which is the expected baseline for full schema coverage.

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 (GET) and resource (one contact), and clarifies what a 'contact' is (driver/technician/employee). The singular 'One contact' implicitly distinguishes it from the sibling fleetio_list_contacts, but the differentiation is not stated explicitly.

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?

Usage is only implied via the singular 'One contact' versus the list_contacts sibling. There is no explicit statement of when to use this lookup by ID versus searching with list_contacts, and no prerequisites are mentioned.

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