List Transit Operators

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

Annotations already declare a safe read (readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=true), so the safety profile is fully covered without the description. The description adds only the scope claim that ALL operators across the five modes are returned, which is mildly useful but not rich 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?

A single front-loaded sentence: resource name first, then scope, then filter capability. No padding or redundancy, though it is terse enough to leave gaps unaddressed.

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?

With only two optional enum parameters, no output schema, and annotations that carry the safety profile, the description covers the essentials for a list tool. It stops short of the routing guidance and default-behavior details an agent would need to choose it confidently over list_ferry_ports or list_community_buses.

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 the description must compensate. It mentions the type filter (種別フィルター) and implicitly ties it to the listed modes, which adds some meaning beyond the raw enum, but it says nothing about the language parameter or how the two optional parameters interact when omitted.

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 names a specific resource (transit operators) and enumerates the covered modes (rail, AGT, monorail, tram, ferry), plus the filter capability. It does not explicitly differentiate itself from overlapping siblings such as list_ferry_ports or list_community_buses, which also surface operator-like listings.

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?

There is no statement of when to use this tool versus the alternatives, and no exclusions. It does not say, for example, whether ferry operators should be fetched here or via list_ferry_ports, leaving the agent to infer routing from the mode list alone.

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