search_route

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

With no annotations, the description carries the full burden and discloses multiple behavioral traits: automatic language identification (Japanese/English/Chinese), detection of weather/high temperature/service suspensions, and returning AI advice. This goes beyond a generic search tool, though it does not specify the output format or confirm read-only behavior explicitly.

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 concise and front-loaded, starting with the core purpose '乗り換えルート検索' followed by a clear explanation and then additional feature notes. It uses a single sentence-like structure with no redundant text, making it easy to parse.

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 only two simple string parameters and no output schema, the description provides a solid high-level overview including output behavior (AI advice) and extra detection features. It does not detail the exact response structure or error handling, but for this complexity it 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?

The input schema already describes both parameters (from and to) as station names with 100% coverage. The description merely restates the departure/arrival station concept without adding further parameter-level detail, so it does not add value beyond the schema.

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 searches for transfer routes from a departure station to an arrival station, which clearly identifies the action and resource. This distinguishes it from sibling tools like search_bus and search_ferry by focusing on rail/station-based route finding.

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 the tool is used for station-to-station route searches but does not explicitly state when to use it versus alternatives such as search_bus, search_ferry, or get_timetable. There is no mention of exclusions or specific scenarios, leaving usage context to be inferred.

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