Create a new analysis session or reset an existing one.
AI agents use create_session to create or update resources in DuckDB MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your DuckDB MCP Server environment.
This tool creates new session objects or modifies existing ones through reset operations, which are reversible write actions. It does not execute arbitrary queries (Execute), delete permanent data (Destructive), or move money (Financial).
From the tool's definition Tool description states 'Create a new analysis session or reset an existing one', indicating it creates or modifies session state. 'Reset' implies modification of existing session data.
Documented attack patterns abuse exactly the kind of access create_session gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and DuckDB MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for create_session:
{
"version": "1",
"default": "deny",
"tools": {
"create_session": {
"limits": [
{
"counter": "create_session_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}create_session 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 new analysis session or reset an existing one. It is categorised as a Write tool in the DuckDB MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the DuckDB MCP Server MCP server in PolicyLayer and add a rule for create_session: 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 DuckDB MCP Server. Nothing to install.
create_session 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_session 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_session. 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_session is provided by the DuckDB MCP Server MCP server (mustafahasankhan/duckdb-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from DuckDB 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.
5 DuckDB MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.