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

With no annotations, the description carries the burden and does disclose return content (old and new rule plus source), result ordering, and cost ('Free'). It does not mention any cap on result count, pagination, or what happens at the edge of the 1460-day limit, which are the remaining behavioral unknowns.

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?

Two sentences with the core purpose front-loaded, followed by the one usage hint and the cost note. No filler and no repetition of the schema.

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?

No output schema exists, and the description compensates by naming the returned fields and ordering. For a two-optional-parameter read tool this is nearly complete, missing only result-size or pagination expectations.

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 both parameters are already documented with ranges and defaults, establishing a baseline of 3. The description adds only marginal meaning ('date window', the past-from_date hint) without clarifying how days and from_date combine into a window.

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?

States a specific verb and resource ('Lists economic nexus threshold changes') plus the scope (date window), ordering (soonest first), and payload (old and new rule and source). The 'changes' framing implies a distinction from the sibling list_nexus_thresholds, but it never names an alternative outright to make the separation unambiguous.

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?

Gives one concrete usage cue: 'Use a past from_date to see recent changes.' There is no guidance on when to prefer this over list_nexus_thresholds or check_economic_nexus, and no statement of when not to use it, so usage remains largely inferred.

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