Export the current canvas to a shareable excalidraw.com URL. The diagram is encrypted and uploaded; anyone with the URL can view it. Returns the shareable link.
AI agents use export_to_excalidraw_url to create or update resources in Excalidraw MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Excalidraw MCP Server environment.
This tool performs a non-destructive data creation action—it uploads and persists the diagram externally. While it doesn't modify existing cloud data or delete anything (ruling out Destructive), it does create a new persistent resource via upload. This falls under Write category.
From the tool's definition The tool uploads diagram data to excalidraw.com and creates a shareable URL, which constitutes creating/modifying a persistent resource (the uploaded diagram on excalidraw.com's servers).
Documented attack patterns abuse exactly the kind of access export_to_excalidraw_url gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Excalidraw MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for export_to_excalidraw_url:
{
"version": "1",
"default": "deny",
"tools": {
"export_to_excalidraw_url": {
"limits": [
{
"counter": "export_to_excalidraw_url_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}export_to_excalidraw_url 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.
Free to start. No card required.
Export the current canvas to a shareable excalidraw.com URL. The diagram is encrypted and uploaded; anyone with the URL can view it. Returns the shareable link. It is categorised as a Write tool in the Excalidraw MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Excalidraw MCP Server MCP server in PolicyLayer and add a rule for export_to_excalidraw_url: 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 Excalidraw MCP Server. Nothing to install.
export_to_excalidraw_url 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 export_to_excalidraw_url 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 export_to_excalidraw_url. 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.
export_to_excalidraw_url is provided by the Excalidraw MCP Server MCP server (yctimlin/mcp_excalidraw). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 26 Excalidraw MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
26 Excalidraw MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.