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

Annotations already declare readOnlyHint=true, so safety is covered; the description adds real value by enumerating the identity fields that come back (account, company, user, timezone) and naming the underlying endpoint. It doesn't say whether ids or raw names are returned, which keeps it from a 5.

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 short sentences: the capability first, then the API reference. Every clause earns its place, with no boilerplate or repetition of the title.

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 no-parameter identity probe with readOnly annotations and no output schema, listing the returned fields goes most of the way toward telling the agent what to expect. A note on response shape (flat vs. nested, id vs. name) would fully close the gap.

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; nothing about the description misleads the agent into passing arguments.

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 concrete verb ('Show') and a precise resource: the account, company, user and timezone of the connected credential. This is clearly distinguishable from every sibling, all of which fetch or list domain entities rather than identity information.

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?

'The connected credential' plus the oauth2/userinfo endpoint makes the use case (verify who you are authenticated as / resolve the current user before other calls) fairly clear without stating it. No explicit when-not-to-use or prerequisites are given, so it falls short of a 5.

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