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

Given that no annotations are provided, the description must carry the full burden of behavioral disclosure. It does disclose a key trait: the tool returns 'all of its printings/variants', which is valuable context. However, it does not mention error behavior, authentication requirements, or any other side effects. For a simple read operation, this is adequate but not exhaustive, so a 3 reflects the partial yet non-trivial disclosure.

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, efficient sentence with zero waste. It front-loads the core purpose ('One card by id') and immediately provides examples and scope ('all printings/variants'). Every part earns its place, and the structure is directly comprehensible.

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 one-parameter getter, the description is complete: it states the purpose, gives ID format examples, and specifies what the response includes (all variants). With no output schema or annotations to rely on, this covers the essential information an agent needs to call the tool correctly. No critical details are missing.

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 provides no description for the 'id' parameter (coverage 0%). The description compensates by giving concrete examples of valid ID formats (en-base1-4, ko-sv4a-190), which clarifies the expected value and helps the agent construct a correct request. This is more than minimal compensation, hence a 4.

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 verb ('get'), resource ('card'), and scope ('by id'), and includes concrete ID examples (en-base1-4, ko-sv4a-190). It also mentions the inclusion of all printings/variants, which distinguishes it from sibling tools like search_cards or list_cards_in_set. The agent can immediately understand what this tool does and when it is the right choice.

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 alternatives. While the description implies that an ID is required, it does not mention when to prefer this over search_cards (e.g., when you already have a known ID) or how it differs from list_cards_in_set. Without exclusions or named alternatives, the agent must infer usage context.

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