mdl_users_get_user_stats

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, covering the safety profile. The description adds no additional behavioral context such as what stats are computed, freshness, or any permission requirements, so it contributes nothing beyond structured fields.

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?

It is a single short sentence with no wasted words, but that brevity comes from under-specification rather than economy of expression. Front-loading is fine but there is almost no content to front-load.

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 no output schema and no annotations describing the return payload, the description should explain what 'stats' comprises. It does not, leaving an agent unable to predict the response shape for a tool whose only input is an identifier.

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%, and the single parameter accepts either a positive integer or a patterned string (username-like). The description says nothing about the user_id format, so it fails to compensate for the schema's lack of 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 'Users: get user stats' essentially restates the tool name (mdl_users_get_user_stats) without defining what 'stats' means. It gives no differentiation from siblings like mdl_users_get_user_info or mdl_users_get_user_watchlist, so an agent cannot tell what data this returns.

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 guidance on when to use this tool versus the many sibling user tools (mdl_users_get_user_info, mdl_users_get_person, mdl_users_get_user_watchlist). The agent is left to guess based on the name alone.

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