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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does not state whether inputs are numeric strings, whether units are expected, whether the output is a number or object, or whether there are constraints on valid inputs. The only behavioral hint is the formula itself, which is a restatement of the purpose rather than additional context.

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 a single, front-loaded sentence that efficiently conveys the core operation. It is not verbose, but it also does not use the available space to add value beyond the formula. It earns its place but could be slightly more informative without becoming bloated.

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 calculation tool with no output schema and no annotations, the description is minimally adequate. It tells the agent what the tool does and what inputs it needs, but leaves open questions about units, input types, and output format. Given the massive sibling catalog and the absence of structured guidance elsewhere, it could do more to help the agent call 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 100%, so the schema already documents both parameters. The description says 'Provide force and area values' and gives the formula, which adds a small amount of semantic meaning (the relationship between the parameters) but does not specify units, formats, or expected value ranges. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb and resource: 'Calculate pressure: force divided by area.' This is clear and unambiguous, distinguishing it from closely-related siblings like x402-force and x402-area by naming the formula. A 5 is reserved for descriptions that also differentiate scope or contrast with alternatives explicitly, which this does not.

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 such as x402-force, x402-area, x402-pressure-unit, or x402-ideal-gas-pressure. The description only tells the agent what the tool computes, not the context or conditions under which it should be selected. For a catalog with hundreds of physics-related siblings, this omission is notable.

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