list_stations

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

No annotations are provided, so the description carries the transparency burden. The description adds meaningful context: it's a read-only operation ('currently in service' implies a snapshot query). It also discloses the return structure (each with id, name, lat, lng), which is helpful behavioral context. However, it doesn't say much about pagination, size limits, or data freshness, which for a list tool could matter.

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, zero waste. The description is front-loaded with the primary purpose and immediately follows with the return structure. Every sentence earns its place. Perfectly sized for a simple listing tool.

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 zero-parameter listing tool with an output schema present, the description is largely complete. It states what's returned (station list with id, name, lat, lng). It could enhance completeness by clarifying data freshness (live vs cached), but given the output schema exists and there are no params, this is quite sufficient.

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 tool has 0 parameters, so there are no params to document. With zero parameters, the baseline of 4 applies. The description's mention of returning id, name, lat, and lng gives useful context about what data shape to expect, which is helpful even without parameters.

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?

Clear verb+resource: 'List all Bixi stations currently in service.' The verb is specific (list), resource identified (Bixi stations), and scope indicated ('currently in service'). Distinguishes from sibling list_rides by naming 'stations' specifically. Could be higher if it contrasted with the sibling, but purpose is explicit and unambiguous.

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 implies usage context (listing stations in service) but provides no explicit guidance on when to use this vs list_rides. While the tool names make the distinction fairly obvious (stations vs rides), there's no explicit when/when-not guidance or mention of alternatives. Adequate implied guidance for a zero-parameter listing tool.

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