list_roster

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

With no annotations, the description fully discloses behavior: that any field can be empty (normal), explains details for groups, dcc_system, dcc_system_name, max_speed_percent scaling, and explicitly states 'No side effects.'

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?

Description is somewhat lengthy but well-organized: begins with purpose and field list, then usage guidance, then detailed field explanations. Every sentence adds value, though could be slightly more concise.

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?

Without an output schema, the description thoroughly explains all return fields and edge cases (empty fields, null values). Covers usage context, side effects, and practical tips. Complete for a list-all tool.

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?

No parameters exist, so schema coverage is 100% trivially. Baseline is 4, and the description does not need to add parameter info because there are none.

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 lists every locomotive in JMRI's roster with specific fields enumerated. It explicitly distinguishes itself from the sibling tool find_locomotive, which resolves names to addresses.

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?

Provides explicit guidance on when to use (before acquire_throttle/set_speed) and when not to (for name-to-address resolution, use find_locomotive). Also explains it's the only way to map loco names to DCC addresses.

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