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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds substantial behavioral context: it compares before/after windows, defines the four return states, explains that 'unknown' means too little data, and explicitly warns that quietness isn't recovery. This goes well beyond the structured 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 compact and dense: question, comparison method, return states, caveat, and beta status all fit in three sentences. The key purpose is front-loaded, and every sentence adds information without redundancy or fluff.

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 only two simple parameters, full annotation coverage, and an output schema, the description covers everything an agent needs: what it measures, when to use it, what results to expect, and the key caveat. No important contextual gap remains.

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 the baseline is 3. The description adds meaning to 'change_applied_at' by explaining it marks the boundary between the 'before' and 'since' windows. It doesn't add prose for 'window_seconds', but the schema already gives bounds, default, and semantic description, so the marginal value is small.

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 uses a specific verb and resource: it answers whether a store's revenue signals actually recovered after a change, and lists the exact signals compared (paid vs pending vs failed order mix, webhook failures, gateway availability). It clearly distinguishes itself from sibling tools like diagnose_revenue_incident or get_checkout_health_snapshot by focusing on post-change verification.

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 explicitly states when to use this tool: 'after a change was made' and 'did this store's revenue signals actually recover?'. It also warns against a common misuse — interpreting quiet time as recovery — and frames the beta/free context. This effectively tells an agent when to choose it over alternatives.

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