find_transit_options

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, and openWorldHint, covering safety and idempotency. The description adds value by mentioning the tool connects to a 'live paid' service, implying external dependency and cost. However, it does not elaborate on rate limits, authentication, or return behavior, which would be beneficial beyond annotations.

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 two sentences long, no fluff. The first sentence states the action, the second provides usage guidance. It is front-loaded and every word earns its place.

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?

Given the tool has 5 optional parameters with zero schema descriptions and no output schema, the description lacks completeness. It does not explain parameters beyond location/transport type, nor describes what the tool returns. The openWorldHint suggests unknown output structure, but the description offers no further context.

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 input schema has 5 parameters with 0% description coverage. The description only hints at 'location' and 'transportation_type' as key parameters, ignoring 'trip_style', 'origin', and 'destination'. With nearly no schema descriptions, the description fails to compensate, leaving agent uncertain about parameter semantics.

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 'connect' and identifies the resource as a 'live paid x402 mobility-options service'. It clearly states when to use it: for transit, rail, ferry, trails, bike/scooter options, or a location-filtered short list. While it doesn't explicitly differentiate from sibling tools, the purpose is distinct and clear.

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 provides explicit guidance on when to use the tool: 'Use when the traveler wants transit, rail, ferry, trails, bike/scooter options, or a location-filtered short list before planning the rest of the trip.' It does not state when not to use or mention 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.