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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the bar is lower; the description still adds the per-token scope and the 2 MB storage-cap context an agent needs to interpret results. It stops short of describing pagination or result ordering, but little else is needed for a zero-argument listing.

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 no filler; scope, contents, and the capacity constraint all appear immediately.

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 annotations covering the safety profile and no output schema present, the description carries the return-shape burden and does so (sizes, remaining space under the cap). Only minor gaps remain, such as ordering or how the cap is reported.

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 no parameters, so there is nothing to disambiguate; baseline 4 applies. No parameter discussion is expected or missing.

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 specific verb (list) and resource (sheets loaded for this token), plus the returned fields (sizes, remaining storage under the 2 MB cap). This clearly separates it from siblings like sheet_info or sheet_stats that target a single sheet or aggregate statistics.

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 'loaded for this token' scoping implies when it applies, but there is no explicit guidance on when to prefer it over sheet_info, sheet_stats, or sheet_find. Usage is inferable rather than stated.

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