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, and it discloses nothing: not whether it is a pure calculation or a network call, not the formula or conventions used (compounding frequency, day count), not any rate limits or required inputs. Zero behavioral information is conveyed.

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?

Four words that are pure duplication of the name; this is under-specification rather than conciseness, so brevity earns nothing. There is no front-loaded information because there is no information.

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 four-parameter financial calculation tool with no annotations and no output schema, the description supplies nothing an agent needs: not the formula, not the input conventions, not the return shape. It is completely inadequate for the tool's complexity.

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%, which sets the baseline at 3, but the schema descriptions are themselves vacuous placeholders ('Face to process', 'Price to process') and all four fields are typed as strings for what are clearly numeric financial inputs. The description adds no semantics at all — it does not clarify units, formats, or which fields are required despite required being empty.

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 'Bond Yield: Bond Yield' — a verbatim restatement of the tool name with no verb, no statement of what is computed, and no indication of the formula or output. It is a tautology rather than a purpose statement, and it does not distinguish the tool from siblings like x402-yield-to-maturity, x402-current-yield, or x402-percent-yield.

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 when-to-use, when-not-to-use, prerequisites, or alternative tools are mentioned. With several closely related yield tools among the siblings (x402-current-yield, x402-yield-to-maturity, x402-dividend-yield, x402-earnings-yield, x402-yield-dashboard), the agent is given no basis for choosing this one over another.

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