Set extra HTTP headers (e.g. User-Agent, Referer) for all subsequent requests in this context. Apply BEFORE navigating.
AI agents invoke crow_browser_set_headers to trigger actions in Crow. 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 modifies the browser/HTTP client context by setting headers that will affect all subsequent requests. It is not merely reading data, nor directly writing persistent data, but configuring runtime behavior that influences subsequent network operations — making it an Execute-category action.
From the tool's definition Set extra HTTP headers (e.g. User-Agent, Referer) for all subsequent requests in this context. Apply BEFORE navigating.
Documented attack patterns abuse exactly the kind of access crow_browser_set_headers gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Crow, and nothing reaches the server without passing your rules. This is the rule we recommend for crow_browser_set_headers:
{
"version": "1",
"default": "deny",
"tools": {
"crow_browser_set_headers": {
"limits": [
{
"counter": "crow_browser_set_headers_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}crow_browser_set_headers 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.
Set extra HTTP headers (e.g. User-Agent, Referer) for all subsequent requests in this context. Apply BEFORE navigating. It is categorised as a Execute tool in the Crow MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Crow MCP server in PolicyLayer and add a rule for crow_browser_set_headers: 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 Crow. Nothing to install.
crow_browser_set_headers 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 crow_browser_set_headers 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 crow_browser_set_headers. 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.
crow_browser_set_headers is provided by the Crow MCP server (kh0pper/crow). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Crow, 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.
576 Crow tools catalogued and risk-classified — across an index of 43,000+ MCP servers.