Scryfall MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool finds synergistic cards but doesn't describe how synergy is determined, what the output format looks like, whether it's a read-only operation, or any limitations like rate limits or permissions. This leaves significant gaps in understanding the tool's behavior for an AI agent.

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, clear sentence that efficiently conveys the core purpose without any wasted words. It is appropriately sized and front-loaded, making it easy for an AI agent to quickly grasp the tool's intent.

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's complexity (8 parameters, no annotations, no output schema), the description is incomplete. It doesn't address behavioral aspects like how synergy is calculated, output format, or usage context. While the schema covers parameters well, the lack of annotations and output schema means the description should do more to guide the agent, but it falls short.

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 input schema has 100% description coverage, so the schema already documents all parameters thoroughly. The description adds no additional meaning beyond the schema, as it doesn't explain parameter interactions or provide examples. However, with high schema coverage, the baseline score is 3, as the schema compensates for the lack of param info in the description.

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's purpose: 'Find cards that synergize with a specific card, theme, or archetype.' It uses a specific verb ('find') and resource ('cards'), and distinguishes itself from siblings like 'search_cards' or 'search_alternatives' by focusing on synergy. However, it doesn't explicitly differentiate from all siblings, such as 'analyze_deck_composition' or 'suggest_mana_base,' which might also involve synergy in broader contexts.

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 explicit guidance on when to use this tool versus alternatives. It implies usage for synergy discovery but doesn't specify scenarios, prerequisites, or exclusions. For example, it doesn't clarify if this is for deck-building, card evaluation, or other contexts, nor does it mention when to choose 'search_alternatives' or 'analyze_deck_composition' instead.

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