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

With no annotations, the description carries the burden and does disclose genuine behavioral context: 'Auth mode: paid' plus exact pricing ($0.005 per call, USDC on Base via x402 or Tempo via MPP) and the POST endpoint. However it says nothing about output shape, limits, rate limits, or error behavior for a tool that has no output schema.

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 content is heavily padded with origin URL, origin hostname, brand boilerplate, provider aliases, family key, repeated keyword lines, and a 'Source description' that duplicates the Summary verbatim. The one actionable sentence is buried, so the reader must scan past noise to find it.

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 tool with no annotations and no output schema, the description covers the commercial/auth dimension well but leaves the functional contract thin: the undocumented 'limit' parameter and unknown return format are gaps an agent needs filled before invoking it confidently.

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 0% across 2 parameters, so the description must compensate but does not. 'text' is only implied by the task, and the 'limit' parameter (default 10) is never mentioned, nor is the input format or how many keywords come back.

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 Summary states a specific verb and resource – 'Extract the most frequent meaningful keywords from Persian text, with stopwords removed' – which clearly identifies the operation within a large sibling set dominated by Persian text utilities. The purpose is unambiguous, though scoping or removal of the metadata padding would sharpen it further.

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?

Three concrete use cases are given ('pull the main topics out of a Persian article', 'extract keywords from a Persian product description', 'summarise what a Persian document is about'), which tell the agent the situations this tool fits. No when-not-to-use or alternative tools are named, so it stops short of a 5.

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