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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds value by disclosing the 2021 suspension gap as a data quirk and explaining the use case of disambiguating empty results. No contradiction with annotations.

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 compact paragraph that front-loads the main output, then gives the critical use case and an example. Every sentence earns its place, though it is slightly longer than strictly necessary for such a simple tool.

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 tool has no required parameters and no output schema, the description covers what it returns (size, date range, gap) and why it matters. The example and use case make it self-sufficient for an agent to call 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 schema documents the single optional _apiKey parameter at 100% coverage, so the description need not repeat it. It does provide an example call (hsr_coverage({})) that illustrates usage but adds no semantics beyond the schema. Baseline 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 states a specific verb ('Report') and resource ('FTC Hart-Scott-Rodino (HSR) early-termination notice dataset'), and lists concrete outputs (count, date range, suspension gap). It clearly distinguishes from siblings like hsr_recent, hsr_search, and hsr_party_history by framing itself as a coverage-check tool.

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 instructs when to call it: 'Call this before treating an empty hsr_recent, hsr_search, or hsr_party_history result as no data'. It also states the purpose of confirming coverage, giving the agent a clear decision rule and naming the alternatives it applies to.

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