get_card

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

With no annotations, the description carries the full burden; it does disclose the payload contents (prices plus per-listing availability), which is genuine behavioral context. However it says nothing about authentication, rate limits, or what happens on ambiguous or unmatched card names.

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?

One front-loaded sentence states purpose and scope, followed by a compact Args block that is warranted because the schema has no parameter descriptions. The example URL earns its space; there is minimal waste.

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 single-parameter lookup with an output schema already covering return values, the description supplies everything needed to call it correctly: purpose, scope, and accepted input formats. Remaining unknowns (error behavior) are minor given the tool's simplicity.

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 0% for the single parameter, and the description compensates well by enumerating the three accepted identifier forms (card name, Scryfall id, ManaPool URL) and giving a concrete URL example. It does not state case sensitivity or name-matching tolerance, so it stops short of a 5.

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 ('Get one card's ManaPool prices and per-listing availability') and makes clear via 'one card' that it is a single-entity lookup, implicitly contrasting with the sibling search_cards. It doesn't explicitly name the sibling, so differentiation is left slightly to inference.

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?

Usage is only implied: an agent can infer this is for fetching details on a known card rather than searching, but there is no explicit 'use this when...' or reference to search_cards as the alternative. No prerequisites or failure conditions are stated.

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