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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, which covers safety. The description adds that it's specifically Lenormand (not Tarot) and lists the types of information returned, which is useful but does not describe the output structure, any potential errors, or pagination. It adds some value but not extensive.

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 a single sentence that is concise and front-loaded. It immediately states the tool's purpose and lists the key output aspects without unnecessary verbosity. Every word adds value.

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 nature of the tool (one required parameter, read-only), the description is complete enough. It specifies the card type, the non-Tarot distinction, and the aspects of information returned. With annotations covering safety and schema covering parameters, the description adds sufficient context for a lookup tool. It could mention the output format or the meaning of the fields, but that may be inferred from the description.

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 input schema fully documents both parameters: 'card' (name, slug, or number) and 'locale' (enum with ru/en, default ru). The description does not elaborate on parameter values beyond what the schema already provides. Since schema coverage is 100%, a baseline of 3 is appropriate.

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 returns a Lenormand oracle card (36 cards, not Tarot) and lists the specific information provided (key, theme in Grand Tableau, essence, love, work, timing). It uses a specific noun (card) and verb (get) and explicitly differentiates from Tarot, which helps distinguish from sibling tools like get_card_meaning.

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 implies usage for Lenormand cards and even notes 'not Tarot', suggesting a contrast with get_card_meaning. However, it does not explicitly state when to use this tool versus alternatives, nor does it mention any prerequisites or context (e.g., 'for general card meanings, use get_card_meaning'). There is minimal guidance beyond the implicit contrast.

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