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

No annotations are provided, so the description carries the full burden and it delivers nothing: no statement of the return type (presumably boolean), no input constraints, no error behavior. For a predicate tool this is a real gap even if the risk is low.

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 consists of a pure tautology with zero informational content — brevity here reflects under-specification rather than efficient structure.

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 no annotations, no output schema, and a generic parameter, the description should at minimum define what an emirp number is or give an example input. Neither is present, so an agent must infer everything from the name.

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% with a single 'value' parameter documented as 'Value to process'. Per the baseline rule, high coverage yields a 3 even when the description adds no parameter detail. The description does nothing to clarify the expected numeric string format, but the schema is nominally complete.

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 Emirp Number: Is Emirp Number' simply restates the tool name twice without adding any explanatory content. A reader can infer it checks whether a number is an emirp, but the description itself contributes no verb/resource clarification beyond the identifier.

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?

No guidance is given on when to use this tool versus the many sibling predicates (is-prime, is-palindromic-prime, is-circular-prime, etc.). No input format, no context, no exclusions.

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