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

With annotations declaring readOnlyHint=true, the description adds valuable context: the calculation (last-7-day vs trailing-28-day norm), the meaning of 50, the update frequency, and the response fields. This goes beyond the annotation without contradicting it, though it doesn't cover potential edge cases or data limitations.

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, front-loading the core definition before usage guidance. Every clause earns its place, with no filler or repetition. It is dense yet readable.

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?

Since there is no output schema, the description helpfully lists the returned components (value, drivers, confidence, methodology_version). It also provides the index formula, update frequency, and usage scenarios. The optional 'days' parameter is not mentioned in the description, but the schema fully covers it, so this is not a significant gap.

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 description coverage is 100%, so the baseline is 3. The single optional 'days' parameter is fully documented in the schema (including the Gold tier requirement and fallback behavior). The tool description itself adds no parameter information, so it neither enhances nor detracts from the 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?

The description clearly states the tool 'Returns a 0-100 US federal litigation activity index' with precise methodology, scale interpretation, and the components returned (value, drivers, confidence, methodology_version). This distinguishes it from the many sibling tools by specifying a unique, concrete metric.

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 explicitly tells when to call: 'when the user asks about federal court filing volume, litigation surges or lulls, or when timing litigation staffing, case intake, or legal-exposure decisions.' It provides clear context but does not mention exclusions or alternatives, so it misses the top score.

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