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

While annotations indicate read-only, idempotent, and open-world behavior, the description adds value by specifying data sources (Muffed's handcuff page and Sleeper) and the exact content (depth chart, injury status). This goes beyond the structured annotations and helps set expectations without contradiction.

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, front-loaded with the core purpose and data sources, and includes a practical use-case question. Every phrase contributes meaning without redundancy.

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 single parameter, no output schema, and rich annotations, the description adequately explains what the tool does and what it returns. It could mention the response format or structure, but for a simple lookup tool the provided context is sufficient to understand and invoke it.

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?

The schema has one parameter 'team' with a full enum of NFL team codes but no property description. The tool description clarifies that the parameter selects a single team's backfield, which is sufficient compensation. The enum itself provides the allowed values, so the meaning is clear.

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 the tool's function: it retrieves a team's backfield handcuff information, depth chart, and injury status. It uses specific verbs like 'answers' and identifies the resource as a specific team's backfield, distinguishing it from sibling tools focused on leagues, players, or metrics.

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 description implicitly defines when to use the tool (to find backup running backs and replacements for injured starters). It does not explicitly name alternatives or exclusions, but the context is clear and distinct from sibling tools.

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