Online players

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It strongly implies a read-only operation by enumerating current-state fields of online players, and it does not hint at any destructive side effects. However, it does not explicitly state read-only behavior, permission requirements, or any data freshness caveats.

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 two short sentences with no wasted words. The first sentence front-loads the exact data fields returned, and the second sentence adds a practical use case. Every part earns its place.

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 zero-parameter read-only tool with no output schema, the description is complete: it enumerates the player fields an agent can expect, implies per-player data, and gives an example scenario. Nothing critical is missing for correct invocation.

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 input schema is empty with zero parameters, so there are no parameter semantics to document. Per the baseline for zero-parameter tools, the description need not compensate for any schema gaps. The description appropriately focuses on the returned data instead.

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 identifies the tool as reporting the names, worlds, block positions, look direction, and gamemode of online players. It lacks an explicit verb like 'lists' or 'returns', but the resource and data fields are unmistakable. It also distinguishes itself from sibling tools, which focus on server info, regions, blocks, and schematics rather than player state.

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 provides a concrete use case: 'Use to pick a build site near someone.' This gives an agent clear context for when the tool is useful. It does not explicitly mention alternatives or when not to use it, but no sibling tool appears to compete with this player-listing function.

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