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

Annotations already declare read-only, idempotent, non-destructive behavior. The description adds important context beyond those annotations: pricing, x402/Solana payment, an HTTPS endpoint, the lo <= hi ordering constraint, and that values past 15 digits are returned as decimal strings. It does not describe error behavior if the ordering constraint is violated, but it adds substantial value.

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 definition is front-loaded with the core operation and example, followed by constraints and output format. The pricing and HTTPS endpoint details add length but are relevant for this x402 tool, so the description is appropriately sized overall.

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 simple two-parameter math tool with no output schema, the description covers scope, inclusive bounds, ordering constraint, an example, output formatting for large values, and access/payment details. It could mention normal integer return behavior or error handling more explicitly, but it is largely complete.

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%, so the description must carry the parameter meaning. It explains that lo and hi define an inclusive range, that lo must not pass hi, and that each index runs from 0 to 100, which meaningfully supplements the schema's min/max constraints.

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 states a specific operation and resource: the sum of involution numbers from lo through hi inclusive, and it gives a concrete example. It is clear what the tool computes, but it does not explicitly differentiate itself from related siblings such as involution, involution_fixed, or involution_mod.

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 gives input constraints and an example, but it does not say when to use this tool instead of related tools like involution or involution_mod. There are no explicit alternatives, exclusions, or use-case guidance.

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