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

Beyond the annotations, the description discloses the key behavior of passing null (clears the locale binding) and caps the blast radius ('does not alter saved designs'), which meaningfully contextualizes destructiveHint=true. It stops short of saying whether the prior locale is recoverable or what the response contains.

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 sentences with zero filler; the positive behavior ('sets... explicit language code') is front-loaded and the null/clear case plus exclusions follow 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 an output schema present and annotations covering the safety profile, the description only needs the locale-null semantics and the scope limits, both of which it supplies. Minor gap: no note on required permissions or what happens to screenshots already localized under a previous locale.

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?

Schema coverage is 0%, so the description must carry the load; it explains the one non-obvious parameter's semantics — locale accepts null to clear the binding — which the schema's anyOf does not convey. folderId and projectId are left entirely to the schema's UUID formats, which is acceptable for identifiers.

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 (sets/clears) on a specific resource (a screenshot folder's locale binding) and explicitly bounds the effect ('does not infer language... or alter saved designs'). An agent can distinguish it from rename_asset_folder or apply_locale_screenshots by this scoping, though no sibling is named outright.

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 implied rather than stated: the agent can infer this is the tool for assigning or clearing a folder's explicit locale, and the 'does not infer from folder name' clause rules out one misreading. There is no explicit 'use when X, use Y instead' routing.

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