Creates a new Shopify customer record with contact details, addresses, tags, notes, and metafields, enabling store admins to add customer profiles via the Admin API.
Create a new customer
| Name | Required | Description | Default |
|---|---|---|---|
| note | No | ||
| tags | No | ||
| No | |||
| phone | No | ||
| lastName | No | ||
| addresses | No | ||
| firstName | No | ||
| taxExempt | No | ||
| metafields | No |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and delivers almost nothing: it does not disclose whether email uniqueness is enforced, whether a duplicate returns an error or silently creates, whether any fields are required, or what the created object looks like. The only inference an agent can safely make is that this is a mutation, which comes from the verb rather than from any stated behavior.
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 single sentence is front-loaded and free of waste, but its brevity is under-specification rather than economy. There is nothing to trim, yet nothing has been invested either.
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 nine-parameter mutation tool with no annotations, no output schema, and 0% schema coverage, the description should explain required vs optional fields and side effects such as duplicate handling. It explains none of this, leaving the agent unable to call the tool correctly without guessing.
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% across nine parameters, including non-obvious ones like metafields (namespace/key/value/type tuples), taxExempt, and the addresses array with provinceCode/countryCode. The description supplies zero parameter meaning, so an agent gets no information about formats, constraints, or which fields matter.
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 ('Create a new customer'), which is immediately distinguishable from its siblings get-customers, update-customer, delete-customer, and customer-merge. It does not explicitly name or contrast with those siblings, but the verb+resource pairing alone 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?
No guidance on when to use this versus update-customer (for existing records) or customer-merge (for deduplication), which is a realistic confusion point given the sibling set. No prerequisites, no mention that all nine fields are optional, so an agent cannot tell what a minimally valid call looks like.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.