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

readOnlyHint=true already signals a safe read, but the description goes further by disclosing the payload shape (account identity plus granted permission scopes such as bookings_rw_all) and framing the call as low-cost. It does not mention auth prerequisites or rate limits, which would be the remaining useful additions.

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?

Three short sentences, each carrying distinct information: what is returned, why to call it, and the underlying endpoint. The return value is front-loaded and nothing is redundant.

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, the description must convey the return contents, and it does so via concrete scope examples. Auth and cost are addressed implicitly. Complete enough to call correctly, though it could say more about the account object's fields.

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 tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. It correctly adds no parameter commentary, which would be noise here.

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+resource: showing which account the credentials map to and which permission scopes were granted. This is unmistakably distinct from every sibling, all of which operate on bookings, customers, payments or products. It stops short of explicitly differentiating itself by name, but no sibling is close enough to warrant it.

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 concrete use case (credential/setup validation, likely as a first call before other operations). It offers no exclusions or alternatives, but none exist in this sibling set. Clear context without explicit when-not guidance.

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