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

Annotations already establish readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds genuinely non-obvious behavior: synthetic/placeholder SKUs are filtered out by default, and rows carry an is_synthetic flag. It does not discuss row volumes, snapshot staleness, or rate limits, but what it adds beyond the annotations is real.

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?

Three tightly packed sentences: output scope first, then the one non-obvious default with its override, then sibling routing. No filler, no restatement of the title, and the most decision-relevant content is front-loaded.

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?

An output schema exists, so return-value explanation is unnecessary, and annotations cover the safety profile. Combined with the default-filtering disclosure and explicit sibling routing, an agent has everything needed to select and invoke this tool correctly without further context.

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 100%, so the baseline is 3. The description goes beyond the schema on the least self-explanatory parameter by defining what 'synthetic' SKUs actually are (reimbursement placeholders) and naming the is_synthetic flag, which the schema only gestures at with an example.

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 first sentence names a specific verb and resource (FBA inventory health snapshot) and enumerates the exact fields returned: age buckets, capped weeks of cover, storage fee risk, sell-through, and Amazon recommended order quantity. It explicitly distinguishes itself from two named siblings, so an agent can differentiate without opening any 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?

It routes explicitly: get_fba_inventory for raw stock counts, get_inventory_risk_triage for cross-signal risk rankings. It also tells the agent when to flip include_synthetic_skus (only when reimbursement placeholder rows are wanted), which is an actionable when-to-use rule rather than an implied one.

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