PetSmart MCP Server

add_to_cart

Add products to your PetSmart shopping cart by providing the product URL, with options to specify quantity and variant selections like size or flavor.

Instructions

Add a product to the PetSmart shopping cart. Optionally specify quantity and product variant (size, flavor, etc.).

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "product_url": "<product_url>"
    },
    "name": "add_to_cart"
  }
}

Input Schema

Name	Required	Description
`product_url`	Yes	Full URL of the PetSmart product page
`quantity`	No	Number of items to add (default: 1)
`variant`	No	Product variant to select (e.g., size, flavor, color)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Mar 15, 2026

TDQS

C2.9/5.0

Behavior2/5

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool adds to a cart but doesn't mention whether this requires user authentication, what happens on success/failure, if there are rate limits, or if the cart persists across sessions. This leaves significant gaps for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose and briefly mentions optional parameters. There is zero wasted text, making it appropriately sized for its purpose.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what the tool returns, error handling, authentication needs, or how it interacts with sibling tools. Given the complexity of e-commerce operations, more context is needed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage is 100%, so the schema already documents all three parameters thoroughly. The description adds minimal value by mentioning optional quantity and variant, but doesn't provide additional syntax, format details, or examples beyond what's in the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Add a product') and resource ('to the PetSmart shopping cart'), making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'checkout' or 'get_product_details', which would require a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'checkout' or 'search_products'. It mentions optional parameters but doesn't specify prerequisites, error conditions, or appropriate contexts for invocation.

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

Deploy Server