Check server setup and credentials

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

Annotations already declare readOnlyHint=true and openWorldHint=true, and the description adds meaningful behavioral context beyond those: it works before credentials exist and returns remediation steps instead of failing. This gives the agent a clear model of the tool's failure semantics without contradicting the annotations.

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?

The description is compact and front-loaded, with the diagnosis scope first and usage conditions following. Each sentence contributes useful guidance, though the final negative instruction could arguably be merged with earlier guidance without much loss.

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 diagnostic tool with no output schema, this description covers the key decision factors: when to call it, when not to, what it checks, why it is unique, and what it returns. There is no missing information an agent would need to invoke or route to this tool 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?

The tool has zero parameters, so the description does not need to explain parameter meaning. The baseline for zero-parameter tools is 4, and the description appropriately focuses on behavior rather than inventing parameter details.

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 uses a specific verb ('Diagnose') and resource ('this server's configuration'), then enumerates exactly what it checks: credential presence, validity against Google, and property reach. It clearly differentiates from sibling tools by noting it is the only tool that works before credentials are configured.

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?

It provides explicit call conditions: after an authentication/permission error, during setup, or when the user asks why it is not working. It also states a concrete negative case—do not use it as a warm-up—and names list_sites as the correct alternative for proving access.

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