Retrieve a customer's contact details, group, loyalty balance, year-to-date spend, addresses, and optional store credit balance by customer ID for account lookups.
One customer (contact details, group, loyalty balance, year-to-date spend) with addresses and, by default, store credit balance.
| Name | Required | Description | Default |
|---|---|---|---|
| customer_id | Yes | ||
| include_store_credit | No |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing the composition of the returned record and the default inclusion of store credit balance, though it says nothing about error behavior when the ID doesn't exist.
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 dense sentence with no filler; the core result (one customer) is front-loaded and the qualifiers follow. Nothing is wasted.
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 the description needn't define return structure, and it correctly focuses on scope and defaults. The only gap for a simple get-by-ID tool is the unspecified identifier format.
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 0%, so both parameters are undocumented in the schema. The phrase 'by default, store credit balance' effectively explains the include_store_credit default, but customer_id's expected format (numeric vs. string, opaque ID vs. email) is never clarified.
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 gives a specific verb-object result (fetch one customer) and enumerates the returned fields: contact details, group, loyalty balance, year-to-date spend, addresses, store credit. 'One customer' implicitly contrasts with the search_customers sibling, but no sibling is named, so differentiation relies on inference.
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: a single-customer lookup by ID. There is no explicit statement of when to prefer this over search_customers or get_customer_group_customers, and no prerequisites or exclusions are mentioned.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.