NS Travel Information MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes the core functionality (real-time arrival information) and output format (list of upcoming arrivals with timing, origin, and status). However, it doesn't mention important behavioral aspects like rate limits, authentication requirements, data freshness guarantees, or error conditions.

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 perfectly concise with two well-structured sentences. The first sentence establishes purpose and scope, while the second clarifies the return format. Every word serves a clear purpose with zero redundancy or unnecessary elaboration.

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 read-only query tool with 5 parameters and no output schema, the description provides adequate but minimal context. It covers the core functionality and return format, but lacks details about error handling, data limitations, or practical usage patterns that would help an agent use it effectively in complex scenarios.

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%, so the schema already documents all 5 parameters thoroughly. The description doesn't add any parameter-specific information beyond what's in the schema. It mentions the general data returned but doesn't provide additional context about parameter interactions or usage patterns.

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 the specific action ('Get real-time arrival information'), resource ('trains at a specific station'), and scope ('upcoming arrivals'). It distinguishes from siblings like get_departures by focusing on arrivals rather than departures, and from get_station_info by providing dynamic arrival data rather than static station details.

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 for checking train arrivals at stations, but doesn't explicitly state when to use this tool versus alternatives like get_departures or get_travel_advice. No specific exclusions or prerequisites are mentioned, leaving the agent to infer appropriate contexts from the tool's purpose.

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