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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds one piece of context beyond that: "비용 없음" (no cost), which tells the agent the call/usefulness is free. It says nothing else about the response beyond listing the topics covered.

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?

One sentence front-loads the returned content categories, and a short second fragment adds the cost constraint. No filler. The phrasing is slightly dense with parentheticals, but every clause carries meaning.

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 a zero-parameter, no-output-schema lookup tool, the description tells the agent what topics the response will cover (MCP connection, API, screen, pricing). This is enough to act on; it only lacks expected response shape and length.

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 tool takes zero parameters and the schema is closed (additionalProperties: false), so there is nothing for the description to disambiguate. Baseline 4 applies.

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 names a specific action (returns guidance) plus the resources: sign-up/connection methods (MCP, API, UI) and pricing plans. It clearly describes a retrieval tool rather than a comparison. It never mentions the sibling try_compare, but the content domains are distinct enough.

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 usage is implied: call it when a user asks how to sign up, connect, or what plans cost. It gives no explicit conditions for when to use it, and no exclusions, and it never routes the agent away from try_compare when a comparison is actually wanted.

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