get_user_sign_ins

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

Given no annotations, the description carries the transparency burden and adds key behavior: the required AuditLog.Read.All permission and the temporal scoping ('within the last N days'). It does not detail output behavior, but the output schema exists to cover that.

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?

Two concise sentences with no redundancy. The first states the core purpose, the second adds the permission requirement. Every sentence 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 simple read-only retrieval tool, the description covers the essential context: purpose, permission, and temporal scope. The output schema handles return values, so no additional detail is required.

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 already provides full descriptions for both parameters (user_id and days). The description only restates the 'within the last N days' concept, adding no new semantic information. So baseline 3 is appropriate.

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?

Clearly states the tool gets sign-in logs for a specific user within a time window, with a specific verb and resource. It distinguishes itself from sibling tools like get_user_audit_logs by specifying 'sign-in logs' versus general audit logs.

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?

Provides a clear context of use (a specific user, recent days) and the required permission, but does not explicitly mention alternatives or exclusion conditions. It is not misleading, just missing explicit when-to-use guidance.

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