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

With no annotations and no output schema, the description carries the full behavioral burden and falls short. It does not disclose the underlying formula (presumably C1V1 = C2V2), whether outputs preserve units, how unit mismatches between volumes are handled, or what shape the result takes. It also does not flag that the schema types are strings, which matters for a numeric calculation.

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?

Two short sentences, front-loaded with the purpose and followed by the input list. No filler or redundancy, though the second sentence is essentially a restatement of the schema properties rather than new 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 no-annotation, no-output-schema calculation tool, the description should specify the formula, unit expectations, and result form. None of these are present, and the parameter list only mirrors the schema. An agent would have to guess at units and at what 'final concentration' is measured in.

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 nominally 100%, but the schema descriptions are pure boilerplate ('FinalVolume to process'), so the description is the only source of real parameter meaning. It names the three inputs and their roles in the calculation, which is the minimum viable clarification; it adds nothing about acceptable formats or units. Baseline 3 is appropriate.

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 names a specific verb and resource: 'Calculate the final concentration after dilution.' An agent can tell this is a chemistry dilution calculation rather than a generic concentration or molarity tool. However, it does not distinguish itself from siblings like x402-concentration or x402-molarity, which sit in the same problem space.

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 sentence 'Provide initialConcentration, initialVolume, and finalVolume' is parameter instruction, not usage guidance. There is no statement of when this tool applies versus alternatives (e.g., x402-concentration, x402-molarity, x402-ratio-simplify), and no prerequisites or exclusions.

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