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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds that it groups orders by email hash, which is a useful algorithmic detail, but it does not discuss limitations (e.g., customers without email hashes) or output specifics. No contradiction, but the added transparency beyond annotations is modest.

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 single, well-structured sentence that front-loads the core action ('Group orders by customer email hash') and then states the purpose. Every word earns its place; there is no filler or repetition.

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 low complexity, a rich output schema, well-documented parameters, and complete annotations (read-only, idempotent, non-destructive), the description covers what the tool does and how. The output schema handles return-value details, and the description supplies enough context for correct invocation without missing prerequisites or vague warnings.

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 input schema provides 100% description coverage, with both 'limit' and 'min_orders' fully explained including defaults and ranges. The description does not repeat or elaborate on these parameters, so it adds no semantic value beyond the schema. The baseline of 3 applies.

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 ('Group orders') and clearly states the goal: finding customers under multiple names or phone numbers. This distinguishes it from siblings like list_customers or get_customer_detail, which would not detect duplicates, so an agent can tell it apart without inspecting schemas.

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 clearly implies when to use the tool (when duplicate customer identities are suspected) and specifies the detection mechanism (email hash). It does not explicitly name alternatives or state when not to use it, but the unique purpose and clear context make the intended usage evident.

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