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

Beyond annotations (readOnlyHint, idempotentHint), the description adds crucial behavior: error handling never raises a protocol error but returns a structured error object, and every call is safe to retry. This gives the agent concrete recovery instructions not present in annotations.

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 reasonably concise and well-structured, with example, usage guidance, error info, and behavioral notes in separate sentences. However, it could be slightly tightened; for instance, the fallback 'after correcting the input it is always safe to retry' is redundant given idempotentHint.

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 tool has an output schema, the description covers what the agent needs: input semantics, usage boundaries, error format, and behavioral guarantees (read-only, idempotent, safe retry). The example return structure matches typical usage. No major gaps.

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 description coverage is 100% with clear descriptions for both 'slug' and 'skill_name'. The description adds an example and a note that skill_name selects one skill, but the schema already provides the core semantics (product slug, exact skill name). Minimal extra value.

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 purpose: 'Load one paid skill's complete instructions from a product.' It specifies the scope (paid skill, not free or all skills) and provides an example input/output. It distinguishes from sibling tools like get_free_skill and get_full_product.

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 explicitly advises when to use this tool ('Use when the caller wants one specific paid skill') and when not to, referencing siblings: 'Not for the free gateway skill... and not for every skill at once (get_full_product).' This provides clear context for selection.

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