evaluate_script
Execute JavaScript
Part of the Chrome DevTools MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
WHEN AI AGENTS USE THIS TOOL
AI agents invoke evaluate_script to trigger processes or run actions in Chrome DevTools. Execute operations can have side effects beyond the immediate call — triggering builds, sending notifications, or starting workflows. Rate limits and argument validation are essential to prevent runaway execution.
WHY ENFORCE A POLICY ON EVALUATE_SCRIPT
evaluate_script can trigger processes with real-world consequences. An uncontrolled agent might start dozens of builds, send mass notifications, or kick off expensive compute jobs. Intercept enforces rate limits and validates arguments to keep execution within safe bounds.
RECOMMENDED POLICY
Execute tools trigger processes. Rate-limit and validate arguments to prevent unintended side effects.
tools:
evaluate_script:
rules:
- action: allow
rate_limit:
max: 10
window: 60
validate:
required_args: trueSee the full Chrome DevTools policy for all 29 tools.
DETAILS
MORE CHROME DEVTOOLS TOOLS
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FREQUENTLY ASKED QUESTIONS
What does the evaluate_script tool do?
Execute JavaScript. It is categorised as a Execute tool in the Chrome DevTools MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
How do I enforce a policy on evaluate_script?
Add a rule in your Intercept YAML policy under the tools section for evaluate_script. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Chrome DevTools MCP server.
What risk level is evaluate_script?
evaluate_script is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Can I rate-limit evaluate_script?
Yes. Add a rate_limit block to the evaluate_script rule in your Intercept 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 evaluate_script completely?
Set action: deny in the Intercept policy for evaluate_script. 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 evaluate_script?
evaluate_script is provided by the Chrome DevTools MCP server (ChromeDevTools/chrome-devtools-mcp). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
ENFORCE POLICIES ON CHROME DEVTOOLS
Open source. One binary. Zero dependencies.