Taiwan Railway station live board

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

Annotations already declare a safe read-only and open-world operation. The description adds useful behavioral context by disclosing that only imminent trains are returned and that delay and platform are included.

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 short, front-loaded with the core purpose, and every sentence contributes either scope clarification or sibling routing. The example is compact and directly relevant.

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 simple one-parameter read tool with a fully documented schema and clear annotations, the description supplies enough detail about scope and returned fields. No output schema is needed, and the key limitation is stated.

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?

The schema already provides 100% coverage for the single station parameter, including name/ID examples. The description's example station adds little beyond what the schema already documents, so the baseline 3 is appropriate.

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 specific verb and resource: trains about to arrive at or leave a TRA station now, with delay and platform. It also distinguishes this live-board tool from the sibling tra_timetable, which covers later trains.

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?

It explicitly limits scope to imminent trains and directs agents to tra_timetable for later ones. The station example further clarifies intended use without leaving the now-vs-later distinction ambiguous.

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