set_performance_budget · Pulspeed MCP: Risk & Policy

WHAT IT DOES

What set_performance_budget does on Pulspeed

AI agents use set_performance_budget to create or update resources in Pulspeed — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Pulspeed environment.

WHY IT NEEDS A POLICY

Why set_performance_budget needs a policy

This tool creates or modifies performance budget configurations—a reversible write operation. It does not delete data permanently (passing null removes budgets but is a configuration reset, not destructive deletion of historical data). It does not execute arbitrary code or trigger financial transactions.

From the tool's definition Tool description states 'Set performance budget thresholds for a site' and 'Pass null to remove all budgets', indicating creation/modification of configuration data. The tool modifies monitoring thresholds that trigger webhook events.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_performance_budget Rate-limited

set_performance_budget 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "set_performance_budget": {
      "limits": [
        {
          "counter": "set_performance_budget_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about set_performance_budget

What does the set_performance_budget tool do? +

Set performance budget thresholds for a site. When a scan violates these thresholds, webhook events (threshold.exceeded, performance.regression) will fire. Pass null to remove all budgets. It is categorised as a Write tool in the Pulspeed MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_performance_budget? +

Register the Pulspeed MCP server in PolicyLayer and add a rule for set_performance_budget: 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 Pulspeed. Nothing to install.

What risk level is set_performance_budget? +

set_performance_budget is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit set_performance_budget? +

Yes. Add a rate_limit block to the set_performance_budget 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 set_performance_budget completely? +

Set action: deny in the PolicyLayer policy for set_performance_budget. 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 set_performance_budget? +

set_performance_budget is provided by the Pulspeed MCP server (pulspeed/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.