get_bus_arrivals

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

No annotations are provided, so the description carries the full burden. It does not disclose that results are real-time/live, how fresh or how many arrivals are returned, or any rate-limit behavior, leaving the agent with only the one-line purpose statement.

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 front-loaded sentence with no filler, which is efficient. It is arguably under-specified rather than overly verbose, but nothing in it is wasted.

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?

There is no output schema and no annotations, so the description should explain what an arrival record contains (line, destination, expected time) and any real-time caveats. For a live-data query tool, that gap leaves the agent unable to set expectations about the response.

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% and the single stopCode parameter is fully documented in the schema, so the baseline is 3. The description adds no format hints or examples beyond what the schema already 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 names a specific verb ('Get') and resource ('next bus arrivals at a bus stop'), which is clear enough to act on. However, it does not differentiate itself from the sibling get_arrivals, leaving the agent to infer the bus-vs-other-mode distinction from the tool name alone.

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?

There is no guidance on when to use this tool versus get_arrivals, get_bus_route, or get_journey_time. No prerequisites or context (e.g., that the stop code must be known in advance) are stated.

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