session_check · Z3/SMT MCP Server MCP: Risk & Policy

WHAT IT DOES

What session_check does on Z3/SMT MCP Server

AI agents invoke session_check to trigger actions in Z3/SMT MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why session_check needs a policy

Based on the server context (Z3 theorem prover) and sibling tools, 'session_check' likely triggers a satisfiability check on the current session's constraints, which is an execution of a solver computation. This is analogous to 'check_sat' but scoped to a session. Since the description is empty, confidence is lowered.

From the tool's definition Tool name 'session_check' on a Z3/SMT server with sibling tools like 'check_sat', 'prove', 'solve' — description is empty and uninformative.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

session_check Rate-limited

session_check stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "session_check": {
      "limits": [
        {
          "counter": "session_check_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Z3/SMT MCP Server, so you can run agents against it safely.

FAQ

Questions about session_check

What does the session_check tool do? +

session_check. It is categorised as a Execute tool in the Z3/SMT MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on session_check? +

Register the Z3/SMT MCP Server MCP server in PolicyLayer and add a rule for session_check: 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 Z3/SMT MCP Server. Nothing to install.

What risk level is session_check? +

session_check is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit session_check? +

Yes. Add a rate_limit block to the session_check 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.

How do I block session_check completely? +

Set action: deny in the PolicyLayer policy for session_check. 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.

What MCP server provides session_check? +

session_check is provided by the Z3/SMT MCP Server MCP server (newjerseystyle/z3smt-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.