Look up a Yu-Gi-Oh! card by name or passcode to retrieve ATK/DEF, Level, type, effect text, and banlist status for accurate card facts.
USE THIS for every individual card fact: name, passcode, ATK/DEF, Level, attribute, type, effect text or banlist status. Look up one card by name or passcode. Do not answer from memory; call this tool first.
| Name | Required | Description | Default |
|---|---|---|---|
| id | No | Card passcode (8 digits) | |
| name | No | Card name (English) |
Changes observed during successful MCP inspections.
v0.10.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the full behavioral burden. It correctly frames this as a retrieval step that should precede reasoning, but says nothing about behavior when a card is not found, whether name matching is fuzzy or exact, or what happens if both name and passcode are supplied.
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?
Three short sentences, front-loaded with the call-to-action and the fact list before the anti-hallucination directive. Nothing is redundant with the title or schema, and every sentence contributes.
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 simple two-parameter read tool with no annotations and no output schema, the description is nearly complete: it names the input modes and enumerates the returned fields, which substitutes for a missing output schema. Only not-found and ambiguity behavior remain uncovered.
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%, so the schema already documents both parameters ('Card passcode (8 digits)' and 'Card name (English)'). The description's phrase 'by name or passcode' adds only that either is acceptable, without resolving precedence when both optional parameters are provided. Baseline 3 is appropriate.
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?
States a specific verb and resource ("Look up one card") and enumerates exactly what facts it returns: name, passcode, ATK/DEF, Level, attribute, type, effect text, banlist status. "One card" implicitly separates it from the sibling ygo_search_cards, so an agent can distinguish it without opening a schema.
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?
"USE THIS for every individual card fact" plus "Do not answer from memory; call this tool first" gives strong, unambiguous when-to-use direction. It stops short of naming an alternative such as ygo_search_cards for multi-card queries, so the exclusion side is only implied.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.