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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered structurally. The description adds genuinely useful operational context – the 10-credit Tier 1 cost and the Tarot: Marseille grouping – but says nothing about determinism via `seed` or how `allowReversed` changes the draw.

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?

Front-loaded and efficient – the spread identity comes first, with cost and grouping as compact bracketed metadata. Nothing is padded, though it is arguably under-specified rather than tight.

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, but a 5-parameter divination tool with zero required parameters and 40% coverage leaves the agent guessing about `question`, `seed` and `allowReversed`. For a draw tool whose whole purpose is generating a reading, this is a real gap.

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 40% (seed, question and allowReversed carry no descriptions), so the description is expected to compensate and does not. It mentions '4-card' but never explains that `question` frames the reading, what `seed` does for reproducibility, or what `allowReversed` controls.

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 artifact – a 4-card spiritual development spread – which is more precise than a bare restatement of the name. It implicitly separates this from the career/love/decision draws in the sibling set by naming the spread's intent, though it never explicitly contrasts 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?

There is no when-to-use guidance, no prerequisites, and no named alternative among the many sibling Marseille draws (draw_cross, draw_hero, draw_seven_card, etc.). The agent must infer from the spread name alone whether this is the right draw for a given request.

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