bulk_card_lookup

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

Annotations (readOnlyHint, openWorldHint, idempotentHint) already indicate safe, idempotent read behavior. The description adds value by detailing the specific output fields (mana cost, type, oracle text, etc.), which goes beyond annotations and helps the agent understand what to expect from the response.

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 two sentences, each earning its place: first states the core purpose, second details return data. It is front-loaded with the action and resource, and contains no superfluous words, achieving high efficiency.

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 simplicity (2 params, 100% schema coverage, clear annotations), the description is largely complete. It covers purpose, input constraints, and output contents. Missing usage guidelines is a minor gap but does not severely impair completeness for this defined-exact-match tool.

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 coverage is 100% with clear parameter descriptions (e.g., case-insensitive name, response_format enum). The tool description merely restates the case-insensitivity already in the schema, adding no new semantic meaning. Baseline 3 is appropriate as the schema already does the heavy lifting.

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 looks up a Magic card by exact name using Scryfall bulk data, and lists specific returned fields. It explicitly mentions 'exact name' and 'case-insensitive', distinguishing it from sibling tools like scryfall_search_cards or bulk_card_search which may offer fuzzy or broader search.

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 does not provide explicit guidance on when to use this tool versus alternatives, nor does it state when not to use it. It implicitly indicates use for exact name lookups, but lacks direct comparisons or exclusion criteria, leaving a gap in usage decision support.

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