Verify credentials and upstream reachability

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

Annotations already declare readOnly/openWorld/idempotent, and the description goes further by disclosing what the response contains (credential source, acceptance, round-trip time, failure-mode hint) and the safety property that it never returns the credential itself. This is meaningful behavioral context beyond the structured fields, and it compensates for the absent output schema.

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 tight sentences with zero filler, front-loading the mechanism before the failure-mode reporting and the trigger condition. 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 diagnostic tool with no output schema, the description fully specifies the returned information and the failure distinctions an agent needs to interpret results, so nothing relevant is missing.

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 there is nothing for the description to disambiguate; the baseline for a no-param tool is 4. Nothing in the text adds or detracts from parameter meaning.

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 states a precise verb+resource: it resolves the credential and makes one authenticated request to iOffice. It is unmistakably distinct from every sibling, all of which are CRUD operations on business entities, by framing itself as the diagnostic/healthcheck path.

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 gives an explicit trigger: "Call this when a real tool fails and you want to know which hop broke." Since no sibling performs diagnostics, no alternative needs to be named, and the when-to-use condition is unambiguous.

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