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

Annotations already declare readOnlyHint=true, and the description adds substantial context: the scoring methodology (share of titles amended), data source (eCFR Versioner API), historical depth (weekly since 1995), and update cadence. No contradictions. It does not discuss rate limits or auth, but for a read-only tool this is well-covered.

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 a single dense sentence plus two short clarifiers. It is front-loaded with the core function, then usage triggers, then update frequency. No wasted words, though the long opening sentence could be split for readability. Still concise overall.

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?

With one optional parameter and no output schema, the description gives the main output fields and the core metric. It does not elaborate on the meaning of each field, but names are self-explanatory. The history behavior is well explained in the schema. Slightly more detail on return structure would be ideal, but it is adequate.

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 baseline is 3. The description itself does not add guidance about the 'days' parameter beyond what the schema already provides (optional history series, Gold tier requirement). No additional parameter semantics are needed.

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 regulatory-change intensity score, explains the underlying metric (share of CFR titles amended in trailing 90 days), and lists output fields. It is specific and distinguishes itself from generic data tools by naming the source, frequency, and scope.

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 lists when to call the tool ('Call when the user asks about regulatory churn, rulemaking or deregulation activity, CFR amendments, compliance risk, or Federal Register volume...'). However, it does not mention when not to use it or name any alternative tools, so it falls short of full exclusion guidance.

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