scryfall_card_rulings

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

Annotations already indicate readOnlyHint=true, idempotentHint=true, and openWorldHint=true, meaning the description adds minimal behavioral context. It confirms the tool returns 'official rulings and clarifications' but does not disclose edge cases (e.g., empty results for unrecognized cards, potential delays, or format limits). The description is consistent with annotations.

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 a single, concise sentence that contains no superfluous words. Every part ('Get', 'official rulings and clarifications', 'for a Magic card') contributes directly to understanding the tool's function.

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?

Given the tool has only one required parameter and no output schema, the description is nearly complete. It would benefit from mentioning the return format (e.g., list of objects with ruling text and date) or behavior when a card has no rulings, but the current information is sufficient for a straightforward lookup.

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 schema has 100% coverage with a single required 'name' parameter described as 'Card name to get official rulings for (exact match)'. The description does not add any semantic value beyond the schema's own description, so it meets the baseline for high schema coverage.

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 clearly states the tool retrieves 'official rulings and clarifications for a Magic card,' specifying verb ('get'), resource ('rulings and clarifications'), and domain ('Magic card'). This distinguishes it from sibling tools that handle card details, prices, or rules lookups.

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 description provides no guidance on when to use this tool versus alternatives like 'rules_lookup' or 'rules_interaction'. There are no exclusions, prerequisites, or context about when rulings are appropriate (e.g., only for official cards, not speculative).

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