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

With no annotations, the description carries the burden and discloses the algorithm (trigram Jaccard), output range, and a concrete cost/payment detail ($0.01 per call, USDC on Base). It does not describe payment flow or error behavior, but for a simple stateless similarity function this is substantially transparent.

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 states the algorithm, input domain, output range, and cost with no wasted text. Every element is relevant to invoking or interpreting the tool.

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 two-parameter function with no output schema, the description provides the return range and cost. It omits interpretation details such as 0 meaning dissimilar and 1 meaning identical, but the Jaccard metric and stated range make the return value sufficiently clear.

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 100%, so the baseline would be 3, but the description adds meaningful domain semantics by specifying that both inputs are Persian strings. It does not explain trigram or normalization handling, but it compensates beyond the schema's generic 'first string'/'second string' labels.

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 names a specific operation and resource: trigram Jaccard similarity between two Persian strings. It also states the output range (0..1), making the tool's purpose unambiguous and distinguishable from all sibling Persian text utilities.

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 metric itself implies the tool's use case, but there is no explicit guidance on when to choose this tool versus other string utilities or when not to use it. No alternatives are named, leaving usage conditions implicit.

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