Account

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

Annotations already cover the full safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds real context beyond them: it discloses that the response uses the legacy `request_status` format and that the data is scoped to the API key's account, both of which affect how an agent should parse the result.

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 tight sentences with the payload contents front-loaded, plus a useful legacy-format caveat. The leading bare word "account" on its own line merely restates the name and earns nothing, which keeps it out of the top band.

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?

With no output schema, the description must carry the return-value burden; it identifies the main response contents and flags the legacy format. It stops short of describing the actual field layout of the `request_status` envelope, but for a 0-param read-only lookup this is nearly complete.

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 and there is nothing for the description to compensate for. Nothing is missing in this dimension.

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 names the resource and its contents specifically: plan, credit balance, and API-key metadata for the account tied to the credential. No sibling tool touches account data, so it is trivially distinguishable, though the verb is implied ("Information about...") rather than stated.

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?

Usage is only implied — an agent can infer this is the tool to call when it needs credit/plan status, and no sibling competes for that role. There is no explicit when-to-use or exclusion statement, so it stays at the implied-usage level.

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