RS-485 Bus Calculator

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

Annotations already confirm readOnly, idempotent, non-destructive behavior. The description adds behavioral context: the rule-of-thumb formula, capping at 1200m, default bias resistor computation, and explicit return structure. This goes beyond the annotations without contradicting them.

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 two sentences plus an example, all front-loaded with key information. Every sentence adds value: formula, constraints, parameter details, and a practical illustration. No redundant text.

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?

Given the output schema exists, the description covers all necessary context: input parameters, default behavior, output fields, and an example. It is sufficient for an agent to use the tool 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?

Input schema has 100% coverage, but the description adds meaning: it explains the rule of thumb linking baud rate to cable length, states that bias_ohm defaults to computed maximum, and provides an example. This enriches the schema documentation.

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 clearly states it calculates RS-485 cable length limit and fail-safe bias resistors. It uses specific verb 'calculates' and resource 'RS-485 bus', distinguishing it from sibling tools which cover different domains like CAN, I2C, or wire sizing.

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 tool name and domain-specific description, but there is no explicit guidance on when to use this tool versus alternatives. Sibling tools are listed but not compared, so the agent 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.