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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds useful context beyond that: it is a cheap/read-only sanity check and it returns account identity plus the granted permission strings, which is the key behavioral payoff.

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 tight sentences front-load the return content before the usage hint, with no filler. The trailing "Bookeo: GET /settings/apikeyinfo." endpoint mapping is mildly redundant but conventional and cheap.

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 must carry the return-value burden, and it does by naming the two returned facts and giving permission-scope examples. A slightly fuller enumeration of possible permission values would make it complete.

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?

Zero parameters, so the baseline of 4 applies; the schema is empty by design and there is nothing further for the description to explain.

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 (show) and resource (Bookoo account + granted permissions for the current credentials), with concrete permission-scope examples. No sibling tool does anything comparable, so it is immediately distinguishable from the CRUD/list/get family.

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?

"A cheap way to confirm the setup works" gives a clear triggering condition for when to call it. It does not name an alternative, but no sibling overlaps this capability, so no exclusion is needed.

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