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

Annotations declare readOnlyHint=true, so the safety profile is already covered. The description adds real operational context: it identifies what the call returns (account and subscription details) and frames it as a diagnostic for auth, shard, and User-Agent correctness, which is beyond what the annotation conveys. It stops short of describing the response structure or failure modes.

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, front-loaded with the resource and purpose, followed by the usage hint and the endpoint. No repetition or filler; 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 zero-parameter read tool with no output schema, the description covers intent, scope, and usage adequately. It could go slightly further in sketching the returned account/subscription fields, but nothing prevents an agent from calling it correctly.

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 is 4 and there is nothing for the description to disambiguate. The mention of the authenticated API key clarifies that credential context is implicit rather than a parameter, which is mild added value.

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 (Get) and resource (Cliniko account and subscription details), scoped to the authenticated API key. No sibling tool touches account/subscription data, so an agent can distinguish it immediately from the appointment/patient/invoice tools. The trailing 'GET /account' endpoint reference reinforces the exact target.

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?

Explicitly recommends itself as 'a good first call to sanity-check auth, shard, and User-Agent,' which is clear usage context. There are no competing siblings to exclude, so the only missing piece is any statement of when not to call it (e.g., after auth is confirmed).

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