Validate a decklist

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

With no annotations, the description carries the burden of behavioral disclosure. It does list the validation checks performed, which is useful. However, it omits what happens on validation failure (e.g., error vs. report), the return format, and any permissions or side-effect details. This leaves gaps in understanding the tool's behavior.

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 sentence that front-loads the core purpose and then specifies all key validation rules. Every clause adds informative detail with no wasted words.

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?

The tool is simple (one parameter, no output schema) and the description covers purpose, input format, and validation rules. However, without an output schema, the description should explain what the tool returns (e.g., validation report, price estimate shape). This missing return-value information makes the description somewhat incomplete for an agent to fully anticipate the tool's output.

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% for the single parameter, giving a baseline of 3. The description adds value by providing an example format ('4 Slowpoke PBL 29') and clarifies the input as TCG Live export format, going beyond the schema's basic 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: 'Validate a TCG Live export decklist' and details specific validation rules (60-card total, max 4 copies per name, ACE SPEC limit, standard legality, price estimate). This distinguishes it from siblings like price_check or build_decks.

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 implies when to use the tool: when an agent has a TCG Live export decklist that needs validation and a price estimate. It provides clear context but does not explicitly mention alternatives or when-not-to-use scenarios relative to siblings.

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