get_train_live_status

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

With no annotations, the description discloses rate limiting and caching, which are important behavioral traits. It does not cover error handling or response structure, but still adds significant value beyond 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?

Two sentences: first sentence states purpose concisely; second sentence provides essential behavioral constraints. Every word earns its place, no redundancy.

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 enumerates key output fields (progress, delays, platforms, position, route geometry), which compensates for the lack of an output schema. For a simple 2-param tool, this is sufficiently complete.

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 100% (both date and train_number have descriptions). The description adds no new parameter-level details; it only restates the overall purpose. 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 explicitly states the tool provides live station-by-station progress, delays, platforms, current position, and route geometry. This clearly differentiates it from sibling tools like get_train_info (static info) and get_train_schedule (planned schedule).

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?

The description includes rate limit (12 req/min) and caching behavior (up to 45s), which guides usage. However, it does not explicitly contrast when to use this tool versus alternatives like get_train_schedule or search_trains for similar tasks.

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