detect_distribution_days

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

Annotations indicate read-only and idempotent. Description adds that it is cache-only with no API call, which is consistent. No contradictions. Could mention error handling but overall good.

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?

Starts with concise purpose, then usage guidelines, see-also, plan info, and parameter descriptions. Every sentence adds value. No redundancy.

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?

Covers usage and parameters well, but lacks explicit description of return value despite context indicating an output schema exists. No mention of error states or edge cases.

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?

With 0% schema coverage, description explains all parameters: date format and default, sigma_multiplier as z-score threshold, window_sessions and min_dist_days with IBD conventions and defaults. Adds meaning beyond schema.

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?

Clearly states it counts TOPIX distribution days in a rolling window, with specific verb and resource. References IBD method and provides Japanese translation for clarity. Distinguished from sibling tools like detect_follow_through_day.

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?

Explicitly states when to use: for distribution day queries, before confirming a follow-through day, and provides threshold (≥4 in 25 sessions). Refers to alternative tool detect_follow_through_day.

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