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

Annotations already establish the read-only, non-destructive nature of the tool. The description adds valuable behavior beyond that: it is a global catalog, search matches name or locale, and returned ids are for tool calls only. This gives the agent practical behavioral context without contradicting annotations.

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?

The description is compact and front-loaded: it states the core purpose first, then filtering, then return value usage and a user-facing formatting rule. Every sentence adds actionable information with no filler.

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 simple optional-parameter read tool with an output schema and safety annotations already provided, this description is complete. It covers the catalog scope, filtering behavior, what information is returned and why it matters, and how to format language references for the user.

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?

The schema only defines 'search' as a string with no explanation. The description fully compensates by explaining the optionality and exact matching semantics: it filters by language name or locale. This is the essential meaning an agent needs to use the parameter correctly.

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 ('List'), a clear resource ('the global Globalize language catalog'), and an optional filtering behavior. It is readily distinguishable from sibling list tools like list_glossary and list_projects.

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 description explains when this tool is needed: it returns the id and locale required to create a project or add a project language. It also gives display guidance for referring to languages. It does not explicitly list when not to use it or name alternatives, but the context is clear enough.

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