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

Annotations already declare the full safety profile (readOnly, idempotent, non-destructive, closed-world), so the description carries a lower burden. It usefully adds the billing fact ('10 credits (Tier 1)') and the endpoint, which an agent needs for cost-awareness. It does not otherwise disclose return format or randomization behavior, but that is largely covered by annotations and the output schema.

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?

Extremely compact and front-loaded: the operative phrase leads, followed by structured bracket tags for group, endpoint, and cost. Nothing is padded. The only weakness is that the brevity comes at the expense of usage guidance, not that any sentence is wasted.

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?

An output schema exists, so return values need not be explained, but the description still leaves meaningful gaps: no guidance on selecting this spread, no explanation of the question/seed/reversed parameters, and no note on determinism despite idempotentHint. For a 6-parameter divination tool surrounded by near-identical siblings, this is thin.

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 only 50%, leaving seed, question, and allowReversed without documented meanings, and the description adds nothing to compensate. Most notably it never mentions the `question` parameter, which is the semantic core of a divination draw, nor the `allowReversed` default. It relies entirely on the schema that is already half-undocumented.

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 resource and shape: 'Five-card linear story spread,' which lets an agent distinguish it from the sibling Lenormand spreads (three_card, 9_card_square, grand_tableau, celtic_cross_lenormand). The name/title reinforce the same verb+resource. It stops short of explicit sibling differentiation in prose, but the spread type is specific enough to route on.

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?

No when-to-use or when-not-to-use guidance is given. It does not say when a five-card linear reading is preferable to the three-card, relationship, or 9-card square spreads that sit right next to it in the catalog. The only routing signal is the spread geometry implied by the title.

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