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

Annotations already declare readOnly, idempotent, and non-destructive, so safety is covered. The description adds a genuinely useful non-schema fact — cost of 10 credits at Tier 1 — but says nothing about how `seed` drives reproducibility 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?

Three short lines, front-loaded with the essential spread definition followed by grouping and cost metadata. No filler, though the bracketed tags are boilerplate rather than explanatory prose.

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, and annotations carry the safety profile. However, with 5 parameters at 40% coverage and no usage guidance, the definition leaves an agent without enough to invoke it confidently for reproducibility or reversal behavior.

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%: `fields` and `precision` are documented in-schema, while `seed`, `question`, and `allowReversed` are bare. The description contributes nothing about any parameter, so it fails to compensate for the coverage gap on a 5-parameter tool.

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?

Names the specific artifact ('7-card horseshoe progression'), which is a distinct spread not shared by any sibling tool, so an agent can tell it apart from the celtic-cross, three-card, and year-ahead draws. The verb 'draw' is only implied via the tool name rather than stated, keeping it out of the top tier.

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 statement of when to choose a horseshoe spread over the many other Rider-Waite spreads (three_card, celtic_cross, decision, relationship), nor any prerequisites such as whether a question is required. Usage must be inferred entirely from the tool name.

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