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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the tool's safety profile is fully covered. The description adds nothing behavioral beyond boilerplate group/cost lines, leaving it with no incremental value on this dimension.

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?

A single short sentence front-loads the core behavior, followed only by bracketed metadata. The group/cost boilerplate is filler, but the useful text is tight and well positioned.

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 no explanation, and the annotations cover safety. The remaining gap is the unresolved ambiguity of whether the result is the full element mapping or the subset matching the required element argument, which matters for correct interpretation of the single required parameter.

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 100% – element, fields and precision are each documented in the schema, including the enum values and the compact-mode path syntax. The description adds no additional parameter meaning, so the baseline 3 applies.

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 the resource (all Minor Arcana cards) and the organizing dimension (element), which partially distinguishes it from siblings like minors, suits_suit and numbers_n. However, it is ambiguous about behavior: it claims 'ALL Minor cards mapped to fire/water/air/earth' while the schema requires a single element, so an agent cannot tell whether it returns the whole element map or only the cards of one chosen element.

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, and no alternatives are named. With sibling lookups by suit, number, court and keyword, the definition should say when an element-based lookup is preferable, but it does not.

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