deck_validate

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

Annotations already indicate read-only, open-world, and idempotent behavior. The description adds value by specifying the tool returns VALID or INVALID with actionable error messages, and lists the specific validation checks performed. This context goes beyond the annotations without contradicting them.

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: first states the main purpose, second lists specific checks and return format. No fluff, front-loaded, and every sentence adds value.

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 description covers the core validation aspects and return format. However, it does not explain that the commander parameter is only required for Commander format (though the schema does), nor does it detail how response_format affects output. Given no output schema, the description could be more explicit about the response structure.

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%, so each parameter is already well-documented. The description adds mention of color identity and singleton rules, which imply the commander parameter is needed for Commander, but this is stated in the schema. No additional parameter semantics beyond what the schema provides.

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 validates a decklist against format construction rules, listing specific checks like legality, deck size, copy limits, color identity, singleton rules, and Pauper rarity. This distinctly separates it from sibling tools such as bulk_format_legality (which checks individual card legality), deck_analysis (which provides deeper analysis), and moxfield_decklist (which imports 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 usage for validating decklist construction but does not explicitly state when to use this tool versus alternatives like bulk_format_legality or deck_analysis. No exclusion criteria or comparative guidance is provided, leaving the agent to infer usage from context.

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