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

Annotations already declare readOnlyHint=true and destructiveHint=false; the description reinforces this ('it switches nothing on') and adds context the annotations don't carry: the no-arg vs query/group response shapes, the fact that returned items include where an admin enables them, and that the Royally wrapper runs it without friction. Useful added context without contradicting the flags.

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?

Front-loaded with what the tool returns and the key usage trigger, then proceeds through modes and the read-only note. Dense and mostly waste-free; slightly longer than strictly necessary, but each sentence carries distinct information.

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 five optional parameters, the description steps up: it describes what the summary mode returns (groups + counts) and what the detail mode returns (items with the enablement location). An agent knows when to call it, how to shape the call, and roughly what comes back.

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 100%, so the baseline is 3, but the description adds real meaning beyond the schema: it explains that no arguments returns groups with counts while `query`/`group` returns enumerated items. The `query` ranking behavior is also described in prose, complementing the schema's own description.

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?

States a specific verb and resource — lists what the site has but has switched off, enumerating the categories (tools, plugin integrations, plugin abilities, external data providers). The line 'None of these is in your tool list' cleanly distinguishes it from the active-tool siblings an agent would otherwise reach for.

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?

Gives an explicit trigger — 'Call it before telling the user that something cannot be done' — which is exactly the situation an agent needs this for. It also explains the two invocation modes. It does not name a specific alternative tool, so it falls just short of the 5 bar.

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