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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered; the description adds genuinely new behavior — nightly refresh cadence, a dated row recorded even when nothing changed, and the shape of returned data (before/after values, dates, counts). It doesn't mention pagination or result ordering, which keeps it short of a 5.

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?

Front-loaded with the core answer (the Drift Ledger feed) before the mechanism and use cases. Mostly earns its length, but the 'real time series, not a guess' flourish is promotional padding that could be cut.

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?

For a single-parameter read-only list with no output schema, the description covers what is returned and how fresh it is. Missing only minor operational detail such as ordering or how to page beyond the 40-item cap.

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 coverage is 0% and the schema shows only a default, but the description supplies the missing bound ('1-40, default 10') and states the semantics — confirmed changes returned. That compensates well for a single parameter, though it's a modest addition.

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 resource and scope: the nightly-measured record of design changes across ~100 reference products. It explicitly differentiates from the sibling get_design_drift by noting that tool is for a single product, so an agent can route without opening either schema.

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 concrete when-to-use cases (answer 'does anyone redesign?', ground a churn claim with a citation, detect a reference has moved) and names the alternative tool plus the condition selecting it ('For one product, call get_design_drift(domain)').

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