MCP Hub

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 successfully describes what data is returned (the statistics breakdown), but fails to mention whether this is a read-only operation, any rate limiting considerations, or error handling behavior when an invalid site is provided.

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 appropriately concise with a single sentence that front-loads the action and resource. Every word earns its place, and the specific metrics listed provide concrete value without redundancy. The '[UNIFIED]' prefix appears to be metadata but does not significantly impact readability.

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 single-parameter tool without an output schema, the description adequately compensates by listing the specific statistics returned (total users, confirmed users, provider breakdown). However, the complete omission of the required 'site' parameter documentation and lack of guidance on output structure (is it an object? array?) leaves clear gaps.

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 schema has 0% description coverage for the required 'site' parameter. Given the low coverage threshold (<50%), the description must compensate by explaining the parameter, but it fails to mention the 'site' parameter entirely, leaving agents without guidance on what value to provide (ID, URL, or name).

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 action ('Get') and resource ('authentication statistics') with specific metrics included (total users, confirmed users, provider breakdown). It implicitly distinguishes from sibling tools like 'supabase_list_users' by emphasizing aggregate statistics rather than individual records, though it could be more explicit about this differentiation.

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 no guidance on when to use this tool versus alternatives such as 'supabase_list_users' or 'supabase_get_auth_config'. There are no prerequisites, no mention of required permissions, and no exclusion criteria provided.

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