RWS: Shadow Card

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

Annotations already establish that this is a read-only, idempotent, non-destructive, closed-world computation. The description adds genuinely useful context beyond them: the credit cost (10, Tier 1) and the POST endpoint. It still does not describe what the returned pair contains or whether the result varies by art set.

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?

The purpose sentence is front-loaded and the remaining content is compact bracketed metadata with no filler. Slightly tag-heavy for a description field, but nothing is redundant.

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 and annotations covering the safety profile, the description covers the minimum: cost, endpoint, required input. It leaves unresolved how `date` is interpreted for a personality-card derivation and how `art` affects output, which are the details an agent most needs here.

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?

The description only repeats that date is required, which the schema already enforces via 'required'. It does not clarify the critical ambiguity of whether date means the birth date used to derive the personality card or the reading date, and says nothing about the art parameter even though schema coverage is only 50%.

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 a specific resource ('shadow card pair') and defines it as the mirror in the major arcana of the personality card, which is more than a restatement of the title. It does not, however, distinguish itself from closely related siblings such as astroway_tarot_rider_waite_soul_personality_card or astroway_tarot_rider_waite_draw_shadow_work, so an agent cannot easily tell which to pick.

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?

The only usage signal is the '[Required: date]' tag and the cost line; there is no statement of when to choose this over the sibling shadow-work or personality-card tools, nor any prerequisite context. Anything about when to use it must be inferred from the parenthetical definition.

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