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

No annotations are provided, so the description carries the full burden of explaining whether the tool is safe, readonly, destructive, or what it returns. It says nothing about behavior: no output, no side-effects, no success/failure conditions, and no hint of what happens when values are passed.

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 text is short, but this is under-specification rather than earned conciseness. A single noun phrase does not give the agent any actionable or structured guidance, especially for a tool with nine optional parameters.

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?

Given nine parameters, no annotations, no output schema, and a large sibling set, the description is far too incomplete. The agent cannot determine which parameter to pass, what result to expect, or how this tool relates to the surrounding shape-check tooling.

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 baseline is 3 and each parameter already has an informative description in the schema. The tool description adds no parameter-level meaning, and it does not clarify which of the nine optional strings contains the 'wo' language tag or why the others are relevant.

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 is a noun phrase, not a statement of behavior: 'ISO 639 language tag wo' mostly restates the tool name in expanded form. It never says whether the tool validates, returns, checks, or normalizes that language tag, and it does nothing to distinguish it from 29 sibling tools.

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?

There is no guidance for when to use this tool versus alternatives, such as wiki-title-ok, file-path-ok, jira-key-shape, or other shape-checking tools. The name and label only weakly imply some language-tag purpose, but the agent is not told when to select it or what alternative to prefer.

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