create_app_info_localization

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

The annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, and the description is consistent with them ('MUTATES'). It adds real value by disclosing the submission prerequisite, but says nothing about what happens on a duplicate locale, whether existing values are overwritten, or what authorization is needed.

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 short sentences with the mutation warning front-loaded and no filler. It is efficient, though the second sentence reads as an imperative instruction rather than clear usage context.

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 five-parameter mutation with zero schema description coverage and no output schema, the description is missing too much: the required appInfoId is never explained, privacyPolicyUrl is unmentioned, and no return or error behavior is described.

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 description coverage is 0% across five parameters, so the description carries the full burden. It names name, subtitle and implicitly locale, but never mentions the required appInfoId or privacyPolicyUrl, leaving the two most opaque parameters undocumented anywhere.

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?

Uses a specific verb+resource ('MUTATES app-level metadata: add a locale') and scopes it to app-level rather than version-level metadata, which distinguishes it from siblings such as create_localization and update_app_info_localization. It never names those siblings explicitly, so the differentiation is implicit rather than stated.

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?

Provides a workflow hint ('Add the same locale to the version before submission') that implies when this tool belongs in a sequence. However, it gives no explicit guidance on when to use this versus update_app_info_localization or create_localization, and no preconditions or failure modes are stated.

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