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

Annotations already flag destructiveHint=true, so the agent knows this is a mutating write. The description usefully adds that the operation is additive rather than an overwrite, and discloses the HTTP verb/path that signals a POST mutation. It does not cover what happens on duplicate translations, permission requirements, or the response shape, so it adds context but not rich behavioral detail.

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 zero filler: the mutation scope and the additive semantics come first, the API mapping second. Every clause earns its place and the key qualifier is front-loaded.

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 write tool with no output schema, the description covers the core action and the additive behavior, which is the essential context. It omits prerequisite/permission information, duplicate-handling behavior, and any indication of what the call returns, leaving meaningful gaps for a mutation tool.

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 100%, so the schema already documents all five parameters including examples for languageId and pluralCategoryName. The description only restates the source-string/target-language relationship without adding format or constraint detail beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb and resource ('Adds a translation for a source string in a target language'), and the 'additive' qualifier distinguishes it from an overwrite-style update. It also maps itself to the underlying Crowdin endpoint, which removes ambiguity about what operation is performed. It stops short of naming a sibling tool for differentiation, so it is clear but not maximally distinguished.

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?

The parenthetical '(additive)' implies this is the right call when creating rather than replacing a translation, which is implied usage guidance. However, there is no explicit when-to-use/when-not statement and no named alternative (e.g. a future update-translation tool) to route the agent. Guidance is present but must be inferred.

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