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

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so the description's added value is the fallback rule: without kilometers the distance is derived from company address to project address. That is genuinely useful behavior disclosure not present in the annotations. Gaps remain on what the response contains and whether repeats create duplicate entries, and the stated automatic calculation sits slightly at odds with the separate calculateDistance flag in the 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?

A single compact sentence that front-loads the action and resource, then lists the core data and the distance fallback. No filler, though the parenthetical and the trailing conditional make it slightly dense to parse.

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 9-parameter mutation with no output schema, the description covers only three fields plus the distance fallback and omits duration, notes, and route addresses entirely. It also does not state what is returned on success, which matters since no output schema exists to compensate. Adequate to call the tool, but with clear gaps.

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 coverage is 100%, so the baseline is 3; the description earns above that by explaining a cross-parameter condition (distanceKm omitted implies auto-calculation from company to project) that the per-field descriptions do not convey. It leaves unexplained how that default interacts with the explicit calculateDistance boolean, and it says nothing about durationMin, notes, or routeFrom/routeTo.

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 concrete verb and resource ("Records a business trip for a project in the logbook (Fahrtenbuch)") and names the key fields captured (date, kilometers, purpose), so an agent knows the write target. It does not explicitly differentiate itself from adjacent creation tools such as createTimeEntry or logVehicleIssue, 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: the tool is for business trips tied to a project in the logbook. There is no explicit statement of when to choose this over createTimeEntry or logVehicleIssue, nor any prerequisite or exclusion. The one embedded condition (omitting kilometers triggers a calculation) is a behavior rule rather than selection guidance.

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