vrchat_group_instances_overview

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

The readOnlyHint annotation already covers safety, so the description adds 'summarize' and 'active' context. However, it does not explain what 'active' means or what the summary entails (e.g., which fields are returned). With annotations present, the bar is lower, and 3 is appropriate.

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 sentence that front-loads the action and resource. It is concise and avoids fluff, though it could be slightly more informative without losing brevity.

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 3 parameters and 0% schema description coverage, the description is insufficient. It does not clarify parameter relationships or the meaning of 'active'. While an output schema exists, the input semantics are missing.

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%, but the description adds no parameter meaning. It does not explain groupId vs shortCode, maxInstances limits, or how they affect results. The description fails to compensate for the lack of schema descriptions.

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 'summarize' and the resource 'active group instances', and labels it read-only. However, it does not differentiate from sibling tools like vrchat_group_members or vrchat_group_events, which could also involve summarizing group data.

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 alternatives (e.g., vrchat_world_instances_overview for worlds). The description only says 'read-only', which is redundant with annotations, but does not give use-case context.

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