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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds genuinely useful non-schema context: the input domain (1–100000), the per-call price ($0.001 USDC via x402 on Solana), and a same-tool HTTPS endpoint. It omits error behavior for out-of-range or non-integer inputs, keeping it from a 5.

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?

Front-loaded with the definition, followed by compact examples, domain limit, and pricing/endpoint — each block earns its place. Slightly verbose in restating the return semantics ('mean is 0 when n is not') for what is essentially a predicate 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?

No output schema exists, and the description compensates by explaining the return value (the harmonic mean, 0 for non-Ore numbers), the numeric domain, and the cost model. An agent can call this correctly without further information; only error/edge-case handling is unspecified.

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 0%, so the description must carry the load: it establishes that n is the integer under test (not a count or modulus), gives the valid range, and explains what a returned value of 0 means. The min/max restates the schema bound, which is redundant but harmless.

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?

States a specific mathematical predicate with a formal definition (n·d(n) divisible by σ(n)) plus worked examples (1→1, 6→2, 140→5, 10 fails), which effectively separates it from the hundreds of sibling number-theory predicates. It stops short of explicitly naming a sibling such as harmonic or abundancy, so it lands just below the top mark.

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?

Usage is implied by the definition — an agent should call it to test/extend an integer for the Ore property — but there is no explicit statement of when to prefer this over related siblings (harmonic, abundancy, divisor_count) nor any exclusions. The reader must infer the appropriate context.

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