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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuine value by listing the returned quantities (RR, OR, 95% CI) in the absence of an output schema, but says nothing about edge-case handling such as zero cells or continuity correction, which materially affects results for this calculation.

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 pipe-delimited format is front-loaded and scannable, with purpose, trigger, aliases and returns in order. The alias list is long and include search keywords rather than semantic guidance, which adds mild bulk but serves discoverability.

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 four-integer read-only calculator with full schema coverage and no output schema, the description covers what it does, when to use it, and what it returns. Only the handling of degenerate table cells is unaddressed, which is a modest gap for a tool of this 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 100%, so the four integer parameters are already documented as counts for exposed/unexposed events and totals. The phrase '2x2 table of counts' reinforces that inputs are raw counts rather than rates or proportions, but no additional guidance (e.g., that totals must be >= events, or ordering conventions) is provided.

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 names the specific measures (risk ratio, odds ratio) and the input form (a 2x2 table of counts), which is more precise than the bare tool name. It is identifiable against statistical siblings like stats_toolbox or roc_auc, though it never explicitly contrasts with them.

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 'USE WHEN: RR, OR and 95% CI from a 2x2 table of counts' clause gives a clear triggering condition, so an agent knows this is the right tool for count-based 2x2 analysis. It stops short of naming exclusions or alternatives (e.g., when to prefer a chi-square or Fisher test tool).

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