lotto_buy_precheck

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

The description reinforces the readOnlyHint annotation by explicitly stating 'never purchases'. It adds useful behavioral context about re-purchase rules (remaining round limit allows additional purchases) and mentions that remaining game count appears in 'round_remaining_games'. This goes beyond minimal annotation coverage.

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 concise and well-structured: it opens with the core purpose (dry run), then explains the limit edge case. Every sentence earns its place and adds meaningful information.

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 has an output schema (not shown but present), so return values are covered elsewhere. The description explains the dry-run behavior, gate decision, limit handling, and remaining game field, making it sufficiently complete for a precheck tool given its simplicity and annotations.

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 already provides a full description for the only parameter 'games' ('number of games (1 game 1,000 won)'), so schema coverage is 100%. The description does not add extra parameter guidance, but that is not needed since the schema fully documents it.

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 it is a 'purchase pre-check (dry run)' that only provides gate decision and next step, never making an actual purchase. This distinguishes it from sibling tools like lotto_draw, which presumably performs the actual purchase.

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 clearly implies this tool is for pre-purchase validation: it 'only tells gate decision and next step' and 'never purchases'. This contrasts with lotto_draw, but it does not explicitly name alternatives or provide explicit when-not-to-use guidance.

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