whoami

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does well: it describes the data returned (account, backend URL, plan, usage meters), discloses a limitation ('when available' for usage meters), notes failure behavior ('Fails with an actionable message if the API key is missing, invalid, or revoked'), and clarifies what it does NOT report. The only minor gap is not describing the exact error/response format, but the disclosure is solid.

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 most important facts (identity, URL, plan, usage). It covers substantial ground in three sentences with zero fluff. Minor deduction because it packs many data points into one long first sentence, making it slightly dense rather than optimally scannable, though still efficient.

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 tool with no output schema, the description is complete: it specifies exactly what data is returned, when to use it, what it does NOT cover (Search Console, with pointer to gsc_status), and failure behavior. There is no under-specification given the tool's simplicity. The description fully addresses its purpose with no gaps.

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 0 parameters, and schema coverage is 100% (empty object schema). Per the rubric, 0 params earns a baseline of 4. The description appropriately focuses on what the tool returns rather than parameters, which is correct for a no-parameter auth/connection check tool.

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 clearly states the tool returns authenticated account identity (email, workspaceId, role), backend URL, plan, and usage meters, with a specific verb ('Return'). It distinguishes itself from siblings by explicitly noting it does NOT report Search Console state and directing users to gsc_status for that, providing clear sibling differentiation.

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 description explicitly says 'Use this first to confirm the connection works', giving a clear when-to-use instruction. It also explicitly excludes a use case ('Does NOT report Search Console state — call gsc_status for that'), naming the alternative tool. This is explicit guidance with a named alternative, meeting the top tier.

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