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

No annotations are present, so the description carries the full burden of explaining behavior, including whether this is a read-only lookup, a generator, or a validator. The tautological text discloses nothing about side effects, input acquisition, output format, or limitations.

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 short but not concisely informative; it is a restatement rather than an explanation. Every word duplicates the name, so the text fails to earn its place.

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 zero parameters, no output schema, no annotations, and only a tautological description, there is insufficient information for an agent to call this tool correctly or understand what result to expect. The description leaves the tool functionally opaque.

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 has zero properties, which normally earns a baseline of 4 since there are no parameters to document. However, the tool name implies some input like letters or a fragment, and the empty schema plus uninformative description leaves ambiguity about whether the tool truly takes no input or whether its input mechanism is undocumented; a brief clarification would be needed for a top score.

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 exactly the tool name restated ('Words Containing: Words Containing'), with no verb and no resource definition. It does not say what the tool computes, what input it expects, or what output it produces, making it impossible to distinguish from siblings like x402-word-prefix or x402-word-suffix.

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 on when to use this tool or when to prefer an alternative. Despite the tool naming convention implying a word-related utility, the description gives no context for selecting it over the many similar word tools in the sibling list.

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