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

With no annotations, the description carries the burden of behavioral disclosure. It clearly signals a read-only listing and specifies the output fields, which is useful. However, it does not mention ordering, potential absence of quays, or any additional behavior beyond listing.

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 a single, front-loaded sentence that states the core action, clarifies terminology, and lists the returned data without redundancies. Every phrase adds information.

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 single-parameter list tool, the description is largely sufficient: it names the input source, the resource being queried, and the output contents. The lack of an output schema is partially offset by the enumerated result fields, though pagination or edge-case behavior is not mentioned.

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 parameter description is detailed with an ID pattern and example. The tool description itself adds little beyond the schema, but since the schema already fully documents stop_place_id, the baseline of 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 uses a specific verb and resource: 'List all quays ... at a stop place' and enumerates the returned data (public codes, coordinates, wheelchair access). This clearly distinguishes it from sibling tools like get_departures or get_stop_accessibility, which address different concerns.

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 clearly implies a use case: querying the platforms of a given stop place. The schema adds the prerequisite 'Get one from resolve_stop_place', giving the agent concrete context for how to obtain a valid stop_place_id. It does not explicitly state when to avoid this tool or name alternatives, but the context is clear.

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