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

Annotations already establish the read-only, non-destructive, closed-world profile, so the description is free to add behavioral context — newest-first ordering, the plan-dependent history window, and the privacy detail that IPs are masked to the network rather than the full address. It stops short of describing pagination behavior when limit caps results.

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 front-loaded sentence, with the actor/subject ('who did what') stated first and the modifier clauses read as one breath. The long dash-separated enumeration is dense but each category earns its place; slightly unwieldy rather than wasteful.

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?

There is no output schema, so the description carries the burden of describing returns, and it does — it states what events appear and their ordering. Combined with annotations covering safety, an agent has enough to call it correctly, though return shape/limit interaction is not spelled out.

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 already 80% and the filter enum values are self-describing, so the baseline is 3. The description earns an extra point by grounding the 'days' parameter in a concrete 7–365 range and by mapping its event categories (logins, people, changes, errors) to the filter values the schema only lists as enum tokens.

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 names a specific verb (get) and resource (activity log) and then enumerates the exact event classes captured — sign-ins, roles, application passwords, updates, edits, PHP errors, failed emails. That enumeration makes it unmistakable against siblings like get_site_health or get_notifications without opening any schema.

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?

Usage is only implied: an agent can infer this is the tool for auditing past site events, and the retention note (7–365 days) implies its boundary, but there is no explicit when-to-use guidance and no named alternative for adjacent needs. Adequate but with a clear gap.

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