Tarot: Decks and Card Art

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

Annotations already declare readOnly, idempotent, closed-world, non-destructive, so the safety profile is covered. The description adds useful non-annotation context — the 5-credit cost and what is actually returned per deck (artist, year, source, card back, missing-card coverage) — but says nothing about result size, ordering, or whether all decks are returned in one response.

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?

One dense sentence plus group/endpoint/cost metadata lines — no filler, and the core statement comes first. The field enumeration is somewhat list-heavy but each item earns its place by telling the agent what the catalog entry contains.

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 no input parameters, the description covers the essentials: what the catalog contains and how the art-set ids are consumed. It does not tell the agent how to get a single deck or spread detail (the *_slug and *_spreads siblings), so routing between this catalog call and the detail endpoints is left unguided.

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 tool takes zero parameters, so the baseline is 4. It goes slightly beyond by explaining that the returned art-set identifiers are what you pass as `art` on tarot routes, which is real semantic value the empty schema cannot convey.

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 precisely: all tarot decks with their spreads plus the public-domain art sets, and enumerates the record fields (id, artist, year, source, preview image, card back, missing-card placeholders). It lacks an explicit verb ('list/retrieve') and does not distinguish itself from deck-specific siblings such as astroway_tarot_rider_waite_spreads or astroway_tarot_marseille_spreads, which an agent could plausibly confuse it with.

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 explicit 'use this when…' or 'do not use for…' statement, and no sibling is named as an alternative. The clause about picking an art set with `art` on any tarot route gives downstream context (this is the catalog you source art-set ids from), which implies usage but leaves the agent to infer when to call it versus the per-deck spreads endpoints.

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