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

No annotations are provided, so the description carries the full behavioral burden. It adds useful context about free trial calls and signed-wallet requirement, but it does not describe return format, precision, valid n range, or behavior for large n.

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 compact and front-loads the core computation before the promotional trial note. The extra free-trial sentence is useful but not strictly necessary, keeping it just short of ideal conciseness.

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 one-parameter math function with no output schema, the formula provides enough to understand the operation. However, it omits the return type and parameter input format, leaving minor but real gaps for an agent invoking it correctly.

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 compensate for the single parameter. It defines n semantically as the upper limit of the sum, which is helpful, but it does not clarify that n is supplied as a string or what string format is accepted.

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 mathematical operation: computes the n-th harmonic number as the sum of 1/k from k=1 to n. This distinguishes it from nearby siblings such as x402-harmonic-mean and x402-harmonic-series by explicitly defining the finite partial sum.

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?

There is no guidance on when to use this tool versus alternatives, nor any exclusions or prerequisites beyond the free-trial note. The mathematical purpose is clear, but the description does not help an agent route between this and related tools.

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