ro_select_char

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 mentions 'enter the world' implying a state change, but it doesn't specify side effects, required prior conditions, error handling for invalid slots, or what happens if no character exists. This is minimal disclosure for a state-changing operation.

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 a single, efficient sentence with no redundant wording. It front-loads the core action ('Select a character') and immediately explains the result. However, it is on the edge of under-specification, but for a one-line description it avoids fluff and gets to the point.

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 tool with only one parameter, no output schema, and no annotations, the description is incomplete. It doesn't mention when it should be used (e.g., after starting the game, after character creation), whether it requires prior login state, or what failures might occur (e.g., invalid slot). An agent would need to infer these from sibling tool names, which is not sufficient.

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 single parameter 'slot' is self-explanatory and the schema defines its integer range and default. The description repeats 'slot number' without adding further meaning or context (e.g., that slot indices correspond to character list order). Since schema coverage is 0% but the parameter is trivial and well-typed, a baseline of 3 is appropriate; the description does not need to overexplain.

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 action ('Select a character by its slot number') and the outcome ('enter the world'), providing a specific verb and resource. It distinguishes the action from other character-related tools like ro_create_char, though it doesn't explicitly name alternatives. The phrasing is unambiguous and directly tied to the tool's function.

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?

No guidance is provided on when to use this tool versus siblings. It doesn't mention prerequisites like needing to start the game first (ro_start), having characters available, or that this is for selecting an existing character after creation. The description gives no context for appropriate invocation or alternatives.

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