user_count

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

With no annotations, the description must carry the burden. It discloses read-only behavior via '[READ]' and performance characteristics via 'cheap health probe', which is useful. It does not mention potential caveats like whether the count is real-time, includes disabled users, or requires specific permissions, leaving some behavioral ambiguity.

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 extremely concise: a short purpose line followed by a one-argument explanation. Every sentence is useful, and the [READ] tag is front-loaded for immediate clarity.

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?

Given the tool's simplicity (one optional parameter, no output schema), the description is nearly complete. It covers purpose, use case, and argument semantics. It does not explicitly describe the return format or edge-case behavior, but 'Total user count' strongly implies a numeric response, making it sufficient for a simple health probe.

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 coverage is 0%, but the description fully compensates by explaining the sole parameter 'target' as an 'IdP target name from config' and stating that omitting it uses the default. This adds essential meaning beyond the raw schema definition.

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 'Total user count in the realm' and labels it as a 'cheap health probe', giving a specific, distinct purpose. It differentiates from sibling list or detail tools by emphasizing it is a count and a lightweight probe.

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 phrase 'cheap health probe' implies usage for health checks and signals low overhead, a clear context. However, it does not explicitly mention alternatives or conditions when not to use it, so there is no direct comparison to sibling tools like list_users.

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