Bypass bot detection and anti-scraping measures
AI agents invoke unblock to trigger actions in Browserless 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.
This tool executes browser automation with deliberate circumvention of anti-bot/anti-scraping defenses on third-party sites. It is not a simple read operation because it actively manipulates browser behavior to evade security measures, which constitutes an external operation with effects dependent on arguments.
From the tool's definition 'Bypass bot detection and anti-scraping measures' — actively circumvents security controls on external websites
Documented attack patterns abuse exactly the kind of access unblock gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Browserless MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for unblock:
{
"version": "1",
"default": "deny",
"tools": {
"unblock": {
"limits": [
{
"counter": "unblock_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}unblock 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.
Free to start. No card required.
Bypass bot detection and anti-scraping measures. It is categorised as a Execute tool in the Browserless MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Browserless MCP Server MCP server in PolicyLayer and add a rule for unblock: 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 Browserless MCP Server. Nothing to install.
unblock is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the unblock 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 unblock. 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.
unblock is provided by the Browserless MCP Server MCP server (lizzard-solutions/browserless-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Browserless 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.
16 Browserless MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.