This function is called when a user wants to update a projection.
AI agents use update_projection to create or update resources in KurrentDB MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your KurrentDB MCP Server environment.
The tool modifies projection configuration and logic, making it a Write operation. While reversible through subsequent updates, the changes can have significant blast radius affecting downstream systems that rely on projection outputs. Severity is high because projection logic errors could corrupt derived data or break dependent queries. Confidence is high based on clear intent to update existing projections.
From the tool's definition Tool name 'update_projection' and description 'This function is called when a user wants to update a projection' indicate modification of existing projection state.
Documented attack patterns abuse exactly the kind of access update_projection gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and KurrentDB MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for update_projection:
{
"version": "1",
"default": "deny",
"tools": {
"update_projection": {
"limits": [
{
"counter": "update_projection_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}update_projection 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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This function is called when a user wants to update a projection. It is categorised as a Write tool in the KurrentDB MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the KurrentDB MCP Server MCP server in PolicyLayer and add a rule for update_projection: 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 KurrentDB MCP Server. Nothing to install.
update_projection 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 update_projection 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 update_projection. 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.
update_projection is provided by the KurrentDB MCP Server MCP server (kurrent-io/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from KurrentDB MCP Server, 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.
8 KurrentDB MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.