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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely new context beyond them: 'No account connection is required,' which tells the agent this call is safe to make before authentication and cannot fail on credential errors.

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?

Three short sentences with zero waste: when to use it, what it returns, and the auth precondition, in that order. The usage cue is front-loaded, which is exactly what an agent needs first.

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 static, zero-parameter read tool with an output schema and full annotation coverage, the description supplies everything an agent needs to decide to call it: purpose, timing, and no-auth requirement. Return-value detail is properly left to the output schema.

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 and the input schema is an empty object, so there is nothing to disambiguate. Baseline for a 0-param tool applies, and the description correctly avoids inventing parameter detail.

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 states a specific resource (supported language codes and labels) and its role, so an agent immediately understands this is a static reference list rather than a project/upload operation. It does not explicitly contrast itself with a named sibling, which keeps it just short of a 5, but the resource is unambiguous against siblings like dub_list_projects.

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?

'Use before choosing a target language' gives an explicit sequencing cue that ties this tool to the translation workflow (e.g. dub_quote_translation). There are no stated exclusions or when-not-to-use conditions, but for a zero-parameter reference lookup little more is needed.

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