get_train_exceptions

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

The description discloses rate limiting (20 requests/minute) and caching (up to 5 minutes), which are behavioral traits beyond the basic purpose. Since no annotations are provided, the description carries the full burden and adequately covers operational constraints, though it does not mention error behavior or auth requirements.

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 exceptionally concise: two sentences covering purpose, usage guidance, and constraints. Every sentence provides necessary information without redundancy.

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's simplicity (one parameter, no output schema, no annotations), the description is complete. It covers what the tool does, how to interpret results, and operational limits. No missing critical information.

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 only parameter, train_number, is fully described in the input schema with pattern and description. With schema coverage at 100%, the baseline is 3. The description adds no extra semantic information beyond what the schema provides.

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 tool retrieves exceptional service information like cancellations or diversions. It uses a specific verb 'Get' and a specific resource 'exceptional service information', distinguishing it from sibling tools like get_train_info or get_train_schedule which serve different purposes.

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 advises to 'Read the returned message field' but does not explicitly state when to use this tool versus alternatives or when not to use it. It provides a usage hint but lacks comparative or contextual guidance with siblings.

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