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

Beyond the destructiveHint annotation, the description discloses meaningful partial-update semantics ('Only the fields you pass are sent'), which matters because the underlying verb is PUT and would otherwise suggest full replacement. It still does not explain what makes the call destructive, whether changes are reversible, or error behavior for an unknown customerId.

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 short sentences, front-loaded with the resource and action, and the partial-update rule is stated immediately after. The trailing 'Shopmonkey: PUT /v3/customer/:id' is marginally useful metadata rather than wasted space.

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 17-parameter mutation with no output schema, the definition covers the core mutation contract but omits return behavior, validation failure handling, and permission/auth requirements. Annotations cover only the destructive flag, so the description leaves real gaps for a write operation.

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% across all 17 parameters, so the schema already documents every field, including the two enums and the country-code pattern. The description's field summary ('name, address, note or preferences') only loosely groups what the schema lists, so baseline 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?

States a specific verb and resource ('Update a customer') and enumerates the field groups affected (name, address, note, preferences). It does not explicitly distinguish itself from sibling mutations like shopmonkey_update_order, but the resource identity is unambiguous.

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: the agent infers this is for modifying an existing customer versus shopmonkey_create_customer. There is no explicit when-to-use condition, no prerequisite statement (e.g., customerId must already exist), and no routing away from alternatives such as shopmonkey_add_customer_email.

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