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

No annotations exist, so the description carries the full burden of behavioral disclosure. It mentions 'efficiently' but does not describe the return value, error behavior, constraints on inputs, handling of negative exponents, or invalid modulus values. For a computational tool this is a meaningful transparency gap.

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 two focused sentences with no filler. It front-loads the operation name and formula, then immediately states what the caller must supply. Every element earns 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 no annotations, no output schema, and an empty input schema, the description should provide a much fuller call contract. It leaves unanswered how the three integers are passed, what the result format is, and how edge cases like zero modulus or large exponents behave. The tool may be simple, but the missing wiring between the described inputs and the empty schema makes it incomplete.

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 input schema is empty, yet the description names the three semantic inputs—base, exponent, and modulus—and explains their role via the formula. This adds value beyond the schema, earning the 0-parameter baseline of 4, though it does not explain how these values map to actual call arguments given the empty schema.

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 clearly identifies the operation as modular exponentiation with an explicit formula (base^exponent mod modulus) and names the required inputs. It is specific enough to distinguish from plain power or modulus tools, though it does not explicitly differentiate itself from siblings like x402-power or x402-mod-related tools.

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 description implies usage whenever modular exponentiation is needed and instructs the user to provide base, exponent, and modulus integers. However, it gives no when-not-to-use guidance, no prerequisites, and no alternatives, leaving usage context mostly implicit.

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