Add text annotation to the topology.
AI agents use gns3_add_text_annotation to create or update resources in GNS3 Network Simulator MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your GNS3 Network Simulator MCP Server environment.
This tool creates a new text annotation element within the GNS3 topology diagram. It is reversible (annotations can be edited or deleted), has no side effects on running simulations or network devices, and does not execute commands or modify network configurations. It therefore falls under Write category (creates data reversibly) rather than Execute or higher severity categories.
From the tool's definition Tool name is 'gns3_add_text_annotation' and description states 'Add text annotation to the topology.' This creates/adds a text element to the GNS3 project visualization.
Documented attack patterns abuse exactly the kind of access gns3_add_text_annotation gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and GNS3 Network Simulator MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for gns3_add_text_annotation:
{
"version": "1",
"default": "deny",
"tools": {
"gns3_add_text_annotation": {
"limits": [
{
"counter": "gns3_add_text_annotation_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}gns3_add_text_annotation 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.
Add text annotation to the topology. It is categorised as a Write tool in the GNS3 Network Simulator MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the GNS3 Network Simulator MCP Server MCP server in PolicyLayer and add a rule for gns3_add_text_annotation: 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 GNS3 Network Simulator MCP Server. Nothing to install.
gns3_add_text_annotation 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 gns3_add_text_annotation 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 gns3_add_text_annotation. 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.
gns3_add_text_annotation is provided by the GNS3 Network Simulator MCP Server MCP server (wael-rd/gns3-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from GNS3 Network Simulator 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.
42 GNS3 Network Simulator MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.