Upload a .zip as site content for your reserved subdomain. Easiest for agents: zip_base64 (base64-encoded zip). Or file_url (public URL to zip). Or file_path (local path, when MCP runs locally).
Risk signalsAccepts file system path (file_path)
Part of the Demo St server.
Free to start. No card required.
AI agents use upload_site to create or modify resources in Demo St. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call upload_site repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Demo St.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"upload_site": {
"limits": [
{
"counter": "upload_site_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Demo St policy for all 5 tools.
These attack patterns abuse exactly the kind of access upload_site gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Upload a .zip as site content for your reserved subdomain. Easiest for agents: zip_base64 (base64-encoded zip). Or file_url (public URL to zip). Or file_path (local path, when MCP runs locally).. It is categorised as a Write tool in the Demo St MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Demo St MCP server in PolicyLayer and add a rule for upload_site: 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 Demo St. Nothing to install.
upload_site is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the upload_site 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 upload_site. 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.
upload_site is provided by the Demo St MCP server (https://demo.st/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 5 Demo St tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.