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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds the data source (SNCB/NMBS) and the kinds of events reported, but says nothing about data freshness, coverage scope, or result size for a live feed. Adequate given the annotation coverage.

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 resource and then the usage condition. The trailing "Example: {}" is slightly odd but does usefully signal that no arguments are required.

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, zero-required-argument lookup with no output schema needs only to say what data comes back and when to call it, both of which are covered. Minor gaps are the absence of any note on data freshness or the language parameter, but nothing essential to correct invocation 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?

Schema description coverage is 0% and the single optional lang parameter (fr/nl/en/de, default en) is never mentioned in the description, so an agent may not realize responses can be requested in Dutch, French or German. The enum values are self-explanatory, which keeps this at baseline rather than lower.

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 resource (current works and disruptions on the SNCB/NMBS network), which is clearly distinct from the sibling tools for stations, departures, connections and train details. It does not explicitly name the siblings it differs from, but the domain separation is obvious from the wording.

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?

"Use when: before advising a train trip in Belgium, to warn about strikes, works or incidents" gives a concrete usage context and enumerates the disruption types covered. No alternatives or exclusions are named, so it falls 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.