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 only the credit cost (10 credits, Tier 1) and the spread composition; it does not explain seed determinism, how allowReversed affects the reading, or whether a question is required.

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 compact sentences plus group/cost tags, front-loaded with the spread identity. Nothing is padded, though the group and cost metadata sit after the substantive content rather than being integrated.

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 described, and all parameters are optional. The description covers the spread's shape and cost, but omits selection guidance against sibling draws and any parameter behavior, leaving modest gaps for a paid draw tool.

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 40% (seed, fields, precision documented; question and allowReversed undocumented), and the description adds nothing about any of the five parameters — not their format, defaults, or effect. With low coverage the description should compensate but does not.

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 — a 6-card Hero's Journey spread with its exact positions (Hero / Objective / two Obstacles / Key / Resolution) and cites its source (Jodorowsky/Costa). That is enough to distinguish it from the many other Marseille draw siblings (cross, decision, love, seven_card, etc.) by spread type, though it never explicitly contrasts itself with them.

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 guidance is given. It does not say which question types or situations call for the Hero's Journey spread rather than, say, draw_decision or draw_celtic_cross, nor any prerequisites. Usage is only faintly implied by the spread's name.

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