Monthly usage

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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds the useful disclosure of what data is returned (per-modality usage against plan limits and current credits), but says nothing about the reporting period, timezone, or whether numbers are refreshed live.

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?

A single front-loaded sentence with the resource first and the informative parenthetical enumerating the return dimensions. No filler, no redundancy with the title or annotations.

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 read tool with no output schema, the description adequately conveys what categories of information come back. Minor gaps remain around freshness and period boundaries, but nothing an agent needs to invoke it correctly 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 the baseline is 4. The description correctly implies a no-argument, account-scoped call rather than introducing any parameter concepts an agent would need to resolve.

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 scope: a monthly usage summary for the account, enumerating the tracked dimensions (analyses, images, videos vs plan limits) plus current credits. That is far more specific than the title 'Monthly usage', though it does not explicitly distinguish itself from the closest sibling, vivid_whoami.

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 use case is only implied: an agent can infer it should call this before or after generating content to check quota. There is no explicit 'use this when' statement and no mention of related tools such as vivid_buy_credits for topping up or vivid_whoami for account identity.

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