Add a new variant to an existing product (size/color/SKU permutation with its own price and inventory).
AI agents use create_variant to create or update resources in Mcp Ap2 — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mcp Ap2 environment.
The tool creates new product variants with pricing and inventory data. While it modifies product catalogs (a Write operation), it does not directly move money or trigger financial transactions—pricing is set but not charged. The operation is reversible.
From the tool's definition Tool description states 'Add a new variant to an existing product' with 'its own price and inventory' — this creates new data (product variant) with associated pricing, which is reversible through deletion or modification.
Documented attack patterns abuse exactly the kind of access create_variant gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mcp Ap2, and nothing reaches the server without passing your rules. This is the rule we recommend for create_variant:
{
"version": "1",
"default": "deny",
"tools": {
"create_variant": {
"limits": [
{
"counter": "create_variant_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}create_variant stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
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Add a new variant to an existing product (size/color/SKU permutation with its own price and inventory). It is categorised as a Write tool in the Mcp Ap2 MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Mcp Ap2 MCP server in PolicyLayer and add a rule for create_variant: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Mcp Ap2. Nothing to install.
create_variant is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the create_variant rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for create_variant. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
create_variant is provided by the Mcp Ap2 MCP server (@codespar/mcp-ap2). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Mcp Ap2, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
1300 Mcp Ap2 tools catalogued and risk-classified — across an index of 43,000+ MCP servers.