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 adds genuine value beyond that by disclosing what the response contains (vehicle, vendor, notes, meter readings, totals) and the underlying GET endpoint, which matters because there is no output schema.

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, zero filler, with the resource and its returned detail front-loaded before the endpoint reference. Every clause earns its place.

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 tool with annotations covering safety and no output schema, the description is nearly sufficient because it enumerates the fields returned. It could still be tighter by noting the id is retrievable from fleetio_list_service_entries, but nothing critical is missing.

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?

Only one parameter, service_entry_id, and schema description coverage is 100% ('Service entry id.'), so the schema does the work. The description adds no format or sourcing detail (e.g., that the id can be an integer or numeric string, or where to obtain it), so this sits at the baseline.

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+resource ('Get service entry' / 'One service entry') and enumerates the detail returned (vehicle, vendor, notes, meter readings, totals). The singular 'One service entry' implicitly contrasts with the fleetio_list_service_entries sibling, but no sibling is named explicitly, so it stops short of a 5.

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: fetching a single known entry by id rather than browsing. There is no explicit when-to-use statement, no mention of when to prefer fleetio_list_service_entries, and no prerequisites (e.g., needing an id obtained from the list tool).

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