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

Annotations already establish readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the active-only scope and the return of p-values and effect sizes, but does not explain what 'active' means or how the 30d-vs-60d result should be interpreted. This is useful context but not rich behavioral detail.

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?

A single front-loaded fragment with no filler; the resource, detection method, and key result fields are packed into one line. Every phrase earns its place.

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 read-only tool with one optional parameter and no output schema, the description partially covers return values via p-values and effect sizes, but not their structure or the meaning of the 30d-vs-60d test. The optional region filter is discoverable in the schema, so this is adequate but not complete.

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%: the only parameter, 'region', has the description 'Theatre slug or label'. The description adds no parameter-level meaning beyond the schema, so the baseline for high coverage applies.

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 phrase 'Active regime shifts (30d-vs-60d test)' identifies a distinct resource and a specific detection method, which separates it from the many sibling query_* tools. It lacks an explicit verb, but the tool name supplies 'query', so the intended operation is clear.

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 gives no when-to-use guidance, alternatives, or exclusions. With 24 sibling tools, an agent must infer that this is the right choice based on the resource name alone.

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