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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered; the closing "Reads only" is largely redundant with that. The description does add real behavioral context beyond annotations: it discloses that the response includes plan/allowance and over-limit state, and it forbids a side-effecting workaround (hand-editing i18n files). It stops short of noting auth requirements or the effect of the branch parameter.

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?

Front-loaded with verb and resource, and the long middle clause is a return-value inventory that earns its place because there is no output schema. Slightly dense as a single sprawling sentence, but there is no filler or repetition apart from the mild redundancy of "Reads only."

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 no output schema, the description carries the burden of telling the agent what comes back, and it does so field by field (direction codes, address prefixes, translation counts, allowance status). Combined with the pre-read ordering and the don't-hand-edit warning, an agent has everything needed to call and interpret it correctly.

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?

Both parameters (projectId, branch) are fully documented in the schema at 100% coverage, including the branch default, so the description need not explain them. It adds no format or selection guidance for either parameter, which is acceptable but not additive.

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?

Opens with a specific verb and resource ("Lists the site's languages") and then enumerates exactly what is returned: setup status, default language, per-language code/name/direction/prefix, translated text counts, hreflang/sitemap address, kit version, and plan allowance. That level of specificity makes it unmistakable against siblings like get_translations and set_translations.

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?

Explicitly sets ordering ("Read it before get_translations or set_translations") and states the when-not path: if languages aren't set up, the owner configures them in Xodia, Project settings, Languages, and the agent must never write src/i18n files or the kit by hand. This is a clear use/avoid instruction with a named fallback.

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