Create a campaign-level negative keyword. Prevents ads from showing for this keyword across entire campaign.
AI agents use ebay_create_campaign_negative_keyword to create or update resources in Ebay — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Ebay environment.
This tool creates/writes marketing data (negative keyword rules) that affects ad delivery across an entire campaign. While reversible (negative keywords can be removed), it modifies business-critical advertising settings and could impact campaign reach and performance if misconfigured by an agent. The blast radius is moderate—misconfiguration affects ad visibility but doesn't delete data or move money.
From the tool's definition Tool creates a campaign-level negative keyword, which modifies campaign advertising settings. The description states it 'Create[s] a campaign-level negative keyword' and 'Prevents ads from showing for this keyword across entire campaign,' indicating…
Risk signalsBulk/mass operation — affects multiple targets
Documented attack patterns abuse exactly the kind of access ebay_create_campaign_negative_keyword gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Ebay, and nothing reaches the server without passing your rules. This is the rule we recommend for ebay_create_campaign_negative_keyword:
{
"version": "1",
"default": "deny",
"tools": {
"ebay_create_campaign_negative_keyword": {
"limits": [
{
"counter": "ebay_create_campaign_negative_keyword_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}ebay_create_campaign_negative_keyword 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.
Free to start. No card required.
Create a campaign-level negative keyword. Prevents ads from showing for this keyword across entire campaign. It is categorised as a Write tool in the Ebay MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Ebay MCP server in PolicyLayer and add a rule for ebay_create_campaign_negative_keyword: 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 Ebay. Nothing to install.
ebay_create_campaign_negative_keyword 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 ebay_create_campaign_negative_keyword 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 ebay_create_campaign_negative_keyword. 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.
ebay_create_campaign_negative_keyword is provided by the Ebay MCP server (yosefhayim/ebay-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 332 Ebay tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
332 Ebay tools catalogued and risk-classified — across an index of 42,500+ MCP servers.