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

Annotations already declare readOnlyHint=true, so the description correctly reinforces a read operation. It adds valuable behavioral details beyond the annotations: the exact formula ('last-7-day vs trailing-28-day baseline'), the '50 = normal pace' benchmark, the list of returned components, and the update cadence ('Updates: daily'). This provides useful behavioral context beyond what the structured annotations convey.

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 three sentences, each with a clear purpose: describe the output, provide usage guidance, and state update frequency. It is front-loaded with the core result ('Returns a 0-100 index'), and every phrase adds value without redundancy. No wasted words.

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?

Given the one optional parameter, full schema coverage, and read-only annotation, the description covers the essential context: what the tool returns, when to invoke it, and how fresh the data is. The output schema is absent, but the description enumerates the key return fields, and the schema covers the historical 'days' behavior. The description is complete for an AI agent to select and use it correctly.

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 description does not elaborate on the optional 'days' parameter, but the input schema already provides full coverage (100%) with a detailed explanation of behavior (history series vs snapshot, Gold tier requirement). The description doesn't add parameter-level meaning beyond the schema, so the baseline score of 3 is appropriate.

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 a specific verb ('Returns') with a precise resource ('US federal rulemaking velocity index') and scope ('0-100... last-7-day vs trailing-28-day baseline'). It also enumerates the returned fields (activity_level, trend, by_type, significant_docs_7d), making it easy to distinguish from sibling tools that likely track other domains.

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 provides explicit when-to-use scenarios: 'Call when the user asks about regulatory surges, slowdowns, midnight rulemaking, or deregulation waves, or when timing compliance staffing, comment-period responses, or policy-sensitive positioning.' This gives clear usage context but doesn't mention when not to use it or alternative tools, so it stops short of a full 5.

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