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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is fully covered. The description's only added behavioral content is the cost (10 credits, Tier 1) and group label, which is useful meta-context but says nothing about output shape or how allowReversed interacts with Lenormand readings.

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?

Two terse lines with the layout semantics front-loaded and no filler; the cost/group metadata is compact. It is efficient, though the terseness arguably comes at the cost of the missing usage and parameter guidance noted elsewhere.

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?

With an output schema present, return values need not be described, and cost/group are covered. However, for a 5-param tool at 40% schema coverage with a meaningful allowReversed flag, the description leaves an agent without enough to invoke confidently beyond the defaults.

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 only 40%: seed, question, and allowReversed have no schema descriptions, and the description adds no parameter meaning at all. allowReversed in particular (default true) is semantically loaded for a Lenormand draw and is left entirely unexplained.

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 explains what the spread's layout means (rows = past/present/future, cols = mind/heart/body), which is genuinely useful and distinguishes this 3x3 square from sibling draws like line_of_five or grand_tableau. It never states the core action (draw nine Lenormand cards), but the name carries that and the layout semantics are specific.

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?

There is no when-to-use guidance, no indication of what question types suit a 9-card square, and no reference to alternatives despite a large family of tarot_lenormand_draw_* siblings (three_card, line_of_five, grand_tableau, celtic_cross). The layout description implies a use case but nothing is stated.

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