Block until a generation completes or fails. Returns final outputs with image paths. Useful for synchronous workflows.
AI agents invoke comfy_wait_for_completion to trigger actions in ComfyUI 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 is classified as Execute rather than Read because it blocks execution flow and is tightly coupled to image generation operations—a computational process with external side effects. The severity is medium because misuse (e.g., indefinite blocking, resource exhaustion) could degrade system responsiveness, but the tool itself does not create, modify, or delete persistent data.
From the tool's definition Tool name 'comfy_wait_for_completion' and description 'Block until a generation completes or fails' indicates it monitors and waits for external image generation operations initiated elsewhere.
Documented attack patterns abuse exactly the kind of access comfy_wait_for_completion gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and ComfyUI MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for comfy_wait_for_completion:
{
"version": "1",
"default": "deny",
"tools": {
"comfy_wait_for_completion": {
"limits": [
{
"counter": "comfy_wait_for_completion_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}comfy_wait_for_completion 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.
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Block until a generation completes or fails. Returns final outputs with image paths. Useful for synchronous workflows. It is categorised as a Execute tool in the ComfyUI MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the ComfyUI MCP Server MCP server in PolicyLayer and add a rule for comfy_wait_for_completion: 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 ComfyUI MCP Server. Nothing to install.
comfy_wait_for_completion 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 comfy_wait_for_completion 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 comfy_wait_for_completion. 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.
comfy_wait_for_completion is provided by the ComfyUI MCP Server MCP server (nikolaibibo/claude-comfyui-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from ComfyUI 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.
14 ComfyUI MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.