Marseille: 22 Majors

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, non-open-world operation. The description adds useful behavioral context beyond that: the endpoint path and a 10-credit Tier 1 cost, which helps the agent reason about expense. It does not describe auth requirements, rate limits, or pagination, but with strong annotation coverage and an output schema, the bar is lower.

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 description is extremely compact and front-loads the resource scope. The bracketed group, endpoint, and cost metadata are structured and easy to parse, with no redundant 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?

For a zero-parameter lookup with an output schema and rich annotations, the description covers the dataset identity and cost. It still lacks context about what the response contains (e.g., whether all 22 are returned with names, numbers, or meanings) and when to prefer this over sibling Marseille lookup endpoints.

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 and the input schema is empty with 100% coverage. There is no parameter semantics to add, so the baseline score of 4 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 identifies the resource and scope ('22 Major Arcana of Marseille deck'), which is more specific than the title alone. However, it omits a verb such as list/get/retrieve, so the agent must infer that this is a catalog lookup rather than a draw or interpretation tool. It does not explicitly distinguish itself from siblings like astroway_tarot_marseille_cards or astroway_tarot_rider_waite_majors.

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 guidance on when to use this tool versus related Marseille endpoints (cards, cards_slug, draw_single, interpret, spreads) or the Rider-Waite majors equivalent. Use is only implied by the resource name, leaving the agent to infer that this is a reference listing rather than a reading or draw.

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