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

Beyond the annotations, the description adds meaningful behavior: it returns exactly one automatically chosen gateway skill, it is free and requires no plan, and invalid input yields a structured {'error': ...} response rather than a protocol error. It also explicitly says calls are read-only and idempotent, making retry safety clear.

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 definition is front-loaded with purpose and usage, then moves to examples and error behavior. It is somewhat long for a one-parameter tool, but nearly every sentence contributes routing, return-shape, or retry 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?

Given the simple one-parameter schema and the existence of an output schema, the description is more than complete. It covers routing to get_full_skill, free access, return shape, error behavior, and retry safety, so an agent has everything needed to invoke 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 coverage is 100%, so the slug parameter is already documented. The description still adds value by showing a typical input, explaining that the skill is chosen automatically from the slug, and giving an error example that routes unknown slugs to list_products.

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: 'Load a product's free gateway skill with its complete instructions.' It explicitly distinguishes this from the product's other skills, which require get_full_skill, so an agent can route correctly without opening sibling schemas.

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?

It gives an explicit use case ('Use when the caller wants usable instructions immediately') and an explicit exclusion plus alternative ('Not for the product's other skills: those are named and need get_full_skill with a skill_name, which requires a paid plan'). It also clarifies that no plan is required for this tool.

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