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

With no annotations, the description carries the full burden and does disclose real side effects: it may charge a price ('pays its price if any') and logs the action to a learning record. These are meaningful behavioral facts an agent needs, though auth requirements beyond the schema and the failure/cost semantics are left implicit.

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?

A single tight sentence that front-loads the core purpose and packs the cost and logging behaviors into a compact parenthetical with zero waste.

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 an action tool that can spend credits and has no output schema, the description should clarify what 'content' is returned and any preconditions. It covers the payment and logging side, but leaves the return shape and cost-failure behavior underspecified.

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 67% with skill_id and api_key documented in the schema. The description adds no parameter-level meaning (e.g., what 'version' does or what forms of skill_id are accepted beyond the schema's own note), so it sits at the baseline where the schema does most of the work.

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?

States a specific verb and resource with scope: 'Use a skill' and it 'returns its content'. This distinguishes it from get_skill by implying consumption/retrieval of content rather than metadata, though it never explicitly names the sibling it differs from.

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 verb 'use' implies the context (consuming a skill rather than browsing or getting), and the parenthetical hints at a cost precondition. But it never states when to prefer this over get_skill or search_skills, leaving the choice to inference.

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