Hva møter jeg på denne bilturen?

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

With no annotations, the description carries the full burden. It discloses important behavioral traits: a forgotten municipality silently removes messages ('en glemt kommune fjerner meldingene der uten å si fra'), time-based evaluation against travel time rather than 'right now', and sorting with the most disruptive first. These go beyond the schema and help set expectations.

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?

The description is well-structured: a clear purpose sentence, followed by practical instructions and caveats. Every sentence earns its place, and bold text highlights the most critical advice. Despite being a bit long, it is dense with useful information and not redundant.

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?

The description covers the tool's core functionality, key parameter choices, and behavioral caveats. The absence of an output schema is partially mitigated by mentioning sorting, but it does not describe the return format or error handling. Given the tool's complexity (7 params), it is reasonably complete, though a bit more detail on output would elevate it.

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?

Although schema coverage is 100%, the description adds significant meaning beyond the field descriptions. It explains the trade-off between 'fylker' and 'kommuner', recommends including 'vei', and clarifies how 'avreise'/'ankomst' affect filtering. This helps the agent choose appropriate values, which is more than the schema alone provides.

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 clearly states the tool's purpose: 'Trafikkmeldinger for en konkret biltur' (traffic messages for a specific car trip). It specifies filtering by route and time, and distinguishes itself from the sibling 'trafikkmeldinger' by being route- and time-specific. The sorting behavior is also mentioned.

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?

Provides clear usage context: define route with counties or municipalities, prefer roads, specify departure/arrival for time-filtering. Gives practical guidance like 'Er du usikker på hvilke kommuner ruta går gjennom, bruk fylker'. However, it does not explicitly name alternatives or state when not to use this tool, so it stops short of a 5.

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