plan_journey

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

No annotations exist, so description carries full burden. It discloses that the tool returns real-time schedules with platform numbers, delays, transfers, and occupancy levels. It also mentions calling multiple times for full day itinerary. Does not mention destructive actions or authentication needs, but overall adequate.

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 with three sentences plus bullet-like usage list. Information is front-loaded with purpose, then usage scenarios, then return details. Every sentence adds value.

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 there is an output schema, description does not need to explain returns. It covers usage, key parameters, and behavior. However, with 8 parameters and only partial description, it could be more thorough. Still adequate for most use cases.

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 0%, so description must compensate. It explains only some parameters: 'from_station', 'to_station', 'via', and 'is_arrival_time'. It does not explain 'date', 'time', 'transport_types', or 'limit'. This partial coverage provides some value but leaves gaps.

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 clearly states it plans a journey through Switzerland by specific transport types. It lists explicit use cases (from A to B, multi-stop, etc.) and the verb 'plan' with resource 'journey' is specific. Distinguishes from siblings like get_booking_link, get_stationboard, search_locations.

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 explicitly says 'Use this whenever someone wants to:' and lists four scenarios. It gives clear context but does not mention when not to use it or compare with alternatives. Parenthetical examples like 'use `via` for intermediate stops' provide guidance.

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