check_train_compatibility

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

With no annotations provided, the description carries the full burden. It discloses the key constraint that exactly one of route or section_ids must be provided, which is valuable. However, it does not mention whether the operation is read-only, any side effects, or behavior around strict_unknown and im_max_train_length_m. It does not contradict annotations (none exist), but it is missing some behavioral context.

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?

Two concise sentences, front-loaded with the tool's main purpose and then usage. Every word earns its place, with no fluff or repetition. Strong structure.

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 moderate complexity and the presence of an output schema (so return format need not be explained), the description covers the primary usage pattern adequately. It misses some parameter details like strict_unknown and im_max_train_length_m, but these are defined in the schema. Overall, it is complete enough for an agent to call the tool correctly in the main intent.

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 schema description coverage is 0% in the description text, so the description must compensate. It explains the relationship and requirement between route and section_ids, adding meaning beyond the bare schema. However, it does not explain train, strict_unknown, or im_max_train_length_m, leaving significant gaps. The partial compensation merits a baseline 3 rather than lower.

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 checks train-route compatibility across gauge, axle load, clearance, and length. It also distinguishes itself from find_route by referencing it as a prerequisite, though it does not explicitly differentiate from siblings like assess_weather_risk. The purpose is specific and understandable.

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 instructs to call find_route first and pass its result, or alternatively pass section_ids for a specific segment. It clearly states that exactly one of the two is required, providing clear when-to-use and when-to-use-alternative guidance. This is exemplary usage direction.

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