Tracerlab

MCP server for Cisco Packet Tracer 9. Lets Claude Code (or any MCP client) build networks in a running Packet Tracer: add devices, cable them, push IOS configs, address everything, set up routing, ping, and find what's broken. It can also read and write .pkt files without Packet Tracer open.

Twelve devices, twelve cables, OSPF across the ring and 6/6 pings, from one prompt.

There are also some ready-made labs (router on a stick, OSPF/EIGRP/RIP topologies, NAT, HSRP, EtherChannel, IPv6) that build in one call.

Install

Needs uv and Packet Tracer 9.

Register the server with your MCP client:

claude mcp add packet-tracer -- uvx --from tracerlab packet-tracer-mcp

Cursor (~/.cursor/mcp.json), VS Code (.vscode/mcp.json) and Codex take the same command:

{
  "mcpServers": {
    "packet-tracer": { "command": "uvx", "args": ["--from", "tracerlab", "packet-tracer-mcp"] }
  }
}

Then install the Packet Tracer side once:

uvx tracerlab install-extension

Restart Packet Tracer and answer Yes when it asks about the new script module. A small "PT-MCP Bridge" window shows up and goes green once the MCP server is running.

If something isn't connecting, run uvx tracerlab doctor.

Use

Open Packet Tracer, start Claude Code and ask for things like:

• build a 3 router OSPF ring with a PC on each LAN and ping everything
• set up router on a stick with VLANs 10, 20, 30 and DHCP
• what's wrong with this network
• show me the running config on R1

examples/enterprise-two-site.pkt is a bigger network built entirely through the tools.

Tests

uv run pytest