localize_apply

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

With no annotations, the description carries the full behavioral burden. It usefully discloses that it *merges* (not replaces) and that 'other locales are ignored' — a silent-filtering behavior worth surfacing. It stops short of saying what happens to existing keys or conflicting values, so coverage is partial.

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 leading with the action and resource, with the format hint tucked into a parenthetical. No filler, though the parenthetical slightly compresses the flow.

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?

An output schema exists, so return values need not be explained, and the definition captures the key nuance (locale filtering, merge). The remaining gap is the undocumented `app_dir` parameter and the lack of notes on overwrite behavior for a mutation with no annotations.

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 compensate. It documents the shape and meaning of `translations` ({english_key: {locale: value}}) beyond the bare type, but says nothing about `app_dir`, whose purpose and expected value remain undocumented in both schema and description.

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+resource: 'Merge translations into the in-app String Catalog'. The phrase 'in-app String Catalog' implicitly separates it from the App Store Connect localization siblings (asc_localize_subscription, asc_localize_group), though it never names them explicitly.

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?

No explicit when-to-use or when-not guidance is given, and no alternative is referenced. The 'apply'/'merge' wording only weakly implies this is the write-back step after translation, leaving the agent to infer when to call it versus the many asc_localize_* siblings.

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