Flatten all layers into a single background layer. Parameters: - image_index: Target image index (default 0) Returns status dict.
AI agents use flatten_image to create or update resources in Gimp — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Gimp environment.
This tool modifies image data by consolidating layers. While not a destructive delete operation (the image and its content persist), flattening removes layer information and structure, making it a Write operation that alters the document state. The severity is medium because the effect is lossy (layer separation is lost) but reversible within the GIMP session via undo, and the base image data remains intact.
From the tool's definition flatten_image: "Flatten all layers into a single background layer." – merges multiple layers into one, modifying the image structure irreversibly in practical terms, though the original image file is not deleted and the operation can theoretically be undone…
Documented attack patterns abuse exactly the kind of access flatten_image gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Gimp, and nothing reaches the server without passing your rules. This is the rule we recommend for flatten_image:
{
"version": "1",
"default": "deny",
"tools": {
"flatten_image": {
"limits": [
{
"counter": "flatten_image_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}flatten_image 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.
Flatten all layers into a single background layer. Parameters: - image_index: Target image index (default 0) Returns status dict. It is categorised as a Write tool in the Gimp MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Gimp MCP server in PolicyLayer and add a rule for flatten_image: 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 Gimp. Nothing to install.
flatten_image 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 flatten_image 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 flatten_image. 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.
flatten_image is provided by the Gimp MCP server (maorcc/gimp-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Gimp, 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.
79 Gimp tools catalogued and risk-classified — across an index of 43,000+ MCP servers.