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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered and the description does not contradict it. The description adds value by enumerating the returned payload (plan, quotas, limits), which matters because no output schema exists. It does not disclose whether the data is live or cached, whether auth is implicit from credentials, or any rate-limit behavior, so it stays at adequate rather than rich.

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 sentence with the resource first and the returned fields enumerated in parentheses, with zero filler. Every clause carries information an agent would otherwise have to infer.

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-argument read-only tool with annotations covering safety and no output schema, the description supplies the essential return content and the scope of the limits. Minor gaps remain: no indication of units or format for the quota values, and no note that the account is inferred from credentials rather than passed in.

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 per the baseline this starts at 4; however the description adds no notes about implicit scoping such as the account being derived from the calling credentials, which is the one semantic an agent might wonder about. The schema is empty and fully covers the (nonexistent) parameter surface.

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 pairs a specific verb ('Show') with a specific resource (the account's plan and usage) and enumerates exactly what is returned: plan, remaining monthly uploads/renders, and limits such as max video length, file size, and watermark. Sibling tools are all caption-job operations, so no overlap exists, though the description never explicitly states that this is the only account-level tool.

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: reporting 'remaining monthly uploads/renders' and 'limits (max video length, file size, watermark)' strongly suggests a pre-flight quota check before submitting an upload or render. There is no explicit when-to-use statement, no mention of alternatives, and no stated caveats about when the numbers might be stale or cached.

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