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

With no annotations provided, the description carries full behavioral burden, and it delivers: it states exactly what is returned (the constant and its value) and its meaning. The only undisclosed detail is the return format/type (number vs string vs object), which is low-stakes for a well-known constant lookup.

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?

One efficient sentence that front-loads the action and value. The 'Avogadro:' prefix slightly duplicates the tool name, but the inclusion of the precise numeric value and definition earns its place.

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 trivial zero-parameter, no-output-schema tool, the description is nearly complete: it names the value the agent will receive and its scientific context. The only gap is the unspecified return type, which is minor since the semantic content of the result is fully stated.

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?

Zero parameters means the baseline is 4. There is nothing to document beyond the empty schema, and the description appropriately explains the meaning of what will be returned rather than parameters.

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 uses a specific verb ('Return') with a clear resource (Avogadro's constant) and includes the exact value (6.02214076 x 10^23) plus the scientific definition. This fully distinguishes it from the many sibling constant tools (boltzmann, planck-constant, faraday-constant) and chemistry-mole tools (molar-mass, moles-from-mass) without ambiguity.

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 explicit when-to-use or alternative-routing guidance is provided. Usage context is only implied by the definition of the constant itself; an agent could in principle confuse it with chemistry calculation tools like molar-mass or mass-from-moles, but the zero-parameter, constant-return nature makes the purpose self-evident enough to infer.

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