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

With no annotations, the description carries the full burden, and it does add real value: the tokenization rule (non-stopword, >2 chars), the default limit, the return contents, and a pricing/quota note (5 free trial calls per signed wallet). It still omits case-sensitivity, stopword list behavior, error modes, and pagination/truncation behavior for large inputs, so it is partial rather than thorough.

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?

A single front-loaded sentence that leads with the verb and packs algorithm, default, and return shape efficiently. The trailing trial-call emoji note is slightly grafted on but costs little.

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?

No output schema exists, so the description usefully summarizes the return (counts plus unique total), which is good. But it leaves the text-vs-input ambiguity unresolved and says nothing about handling of empty or oversized input, which matters for a text-processing tool with 0% schema documentation.

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 coverage is 0%, so the description must compensate for all three params, but it only explains limit (default 10). The schema exposes both text and input with no description, and the description never clarifies which one is consumed or whether they are aliases — a genuinely ambiguous point the agent must guess at.

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?

States a specific verb and resource ("Extracts ... most frequent non-stopword tokens over two characters") and even specifies the output shape (counts plus unique total). However, it never distinguishes itself from near-identical siblings such as x402-word-frequency, x402-keywords, or x402-keyword-density, so the agent gets no help choosing among them.

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 when-to-use, when-not-to-use, or alternative-tool guidance at all. The only usage-adjacent detail is the default limit of 10, which is a parameter default rather than invocation context.

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