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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful context beyond them: that deprecated customers are still returned, that prices are opt-in, and the underlying GET route.

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?

A single compact sentence with the key facts (scope, deprecated records, optional expansion) front-loaded. The trailing 'GET /customer?ID=…' route fragment is arguably dead weight for an agent choosing a tool, but it is short and harmless.

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 simple two-parameter lookup with no output schema, the description conveys what is fetched and which optional expansion exists, and annotations cover the read-only safety profile. Return field details are omitted, but a single-entity GET is low risk.

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 in the schema; baseline is 3. The description restates include_product_prices in prose ('optionally with its customer-specific product prices') but adds no format, syntax, or edge-case detail beyond it.

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 ('One customer by id') and clarifies scope ('including deprecated ones') plus the optional payload ('customer-specific product prices'). It is clearly distinguishable from list-style siblings, though it never names cin7core_list_customers explicitly.

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?

Usage is only implied by the singular framing ('one customer by id'), which suggests lookup-by-known-id rather than listing. There is no explicit statement of when to prefer this over cin7core_list_customers or any prerequisite/permission guidance.

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