Model Context Protocol (MCP) Server for Cisco Packet Tracer

Name: Cisco Packet Tracer
Rating: 80.3 (1 reviews)
Author: kiskander

mcp-name: io.github.kiskander/pt-mcp-server

Overview

pt-mcp brings AI assistants to your Packet Tracer labs. It lets you work with a running Cisco Packet Tracer in natural language from AI applications like Claude Desktop, Claude Code, and Cursor.

Instead of dragging devices around and typing every command by hand, tell the AI what you want in plain English, like "Build two routers with a serial link and static routes, then prove the PCs can ping each other" or "Step my ping through simulation mode and explain what the switch does with the frame". Then watch it happen in Packet Tracer.

This works through the Model Context Protocol (MCP), a standard way for AI applications to use external tools. pt-mcp connects to Packet Tracer through Packet Tracer's own external-application interface: the IPC API over PTMP, the same channel Cisco's "ExApps" use. That means no plugins inside Packet Tracer, no patched binaries, and no screen scraping.

It is built with CCNA students in mind. It can show you why the network behaves the way it does (Packet Tracer's own per-hop explanations in simulation mode), it verifies the way the exam expects, and by design it cannot read the answers or score of a graded activity.

Features

Build Topologies: Add devices, cable them (with automatic cable selection like the GUI), or build an entire lab (devices, expansion cards, cables, host IPs, IOS configs) in one call.
Export and Rebuild Labs: Export the open network, configs included, in the same format, and rebuild it anywhere.
Configure Devices: Paste whole IOS configs (show running-config output works as-is), run exec or config commands, and get each command's status. Read, save, and erase running and startup configs.
Expansion Modules: See a device's slots and supported cards (HWIC-2T, NIM-2T, WIC, SFPs…) and install or remove them. Power cycling is handled for you.
End Devices: Set PC/server IP settings, and run Command Prompt commands (ping, ipconfig, tracert) with their output.
Verify Connectivity: Ping matrices with loss statistics, retrying the usual ARP/STP first-ping failures.
Simulation Mode (Packet Tracer's "packet capture"): Send PDUs, step time, list events, and read Packet Tracer's own OSI-layer explanation of each hop plus decoded headers (Ethernet, 802.1Q, IP, ICMP, ARP, HDLC, TCP/UDP, STP, OSPF, DHCP, DNS, CDP…).
Console and Command Logs: Read a device's console buffer (%LINK/%LINEPROTO messages) and Packet Tracer's log of typed commands.
Annotations: Add, edit, and delete notes, lines, and circles on the logical workspace.
Activities (.pka): Read an activity's instructions. Answers and scores are deliberately out of reach.
Crash Protection: Only IPC calls verified against a live Packet Tracer are ever sent, and known crashing calls are blocked (see Crash protection).
Cross-Platform: Tested on macOS and Windows with Packet Tracer 9.0.1. .pkt files move between them.
Modular Architecture: Tools are organized into modules (devices, links, cli, simulation, etc.), following cml-mcp.

Quick Start

Requirements

Cisco Packet Tracer 9.0.1, running and logged in to NetAcad (8.2.0 API data is included but not re-verified)
macOS or Windows (Linux is detected but untested)
uv, which brings its own Python (3.12–3.14)
git, which uvx uses to fetch the server from GitHub

Step 1: Register `pt-mcp` with Packet Tracer (one time per computer)

uvx --from git+https://github.com/kiskander/pt-mcp-server pt-mcp setup

This finds Packet Tracer, generates a private key for this computer, creates PTMCP.pta in a pt-mcp folder in your home folder (~/pt-mcp/ or C:\Users\<you>\pt-mcp\), and opens that folder for you.

Then in Packet Tracer:

Extensions → IPC → Configure Apps… → Add
Choose PTMCP.pta from the pt-mcp folder
Accept the prompt and leave it on On Demand

Step 2: Check the connection

uvx --from git+https://github.com/kiskander/pt-mcp-server pt-mcp doctor

Every line should say [OK]. If one doesn't, it tells you how to fix it.

Step 3: Add the server to your MCP client

Copy the block for your client into its MCP configuration file. No keys or passwords go here: the server reads the key that setup saved.

Claude Desktop: claude_desktop_config.json (macOS ~/Library/Application Support/Claude/, Windows %APPDATA%\Claude\, Linux ~/.config/Claude/)

{
  "mcpServers": {
    "Cisco Packet Tracer": {
      "type": "stdio",
      "command": "uvx",
      "args": ["--from", "git+https://github.com/kiskander/pt-mcp-server", "pt-mcp"]
    }
  }
}

Claude Code: .mcp.json in your project (or run claude mcp add --scope user packet-tracer -- uvx --from git+https://github.com/kiskander/pt-mcp-server pt-mcp)

{
  "mcpServers": {
    "packet-tracer": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/kiskander/pt-mcp-server", "pt-mcp"]
    }
  }
}

Cursor: ~/.cursor/mcp.json (or .cursor/mcp.json in a project)

{
  "mcpServers": {
    "packet-tracer": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/kiskander/pt-mcp-server", "pt-mcp"]
    }
  }
}

VS Code (GitHub Copilot): .vscode/mcp.json

{
  "servers": {
    "packet-tracer": {
      "type": "stdio",
      "command": "uvx",
      "args": ["--from", "git+https://github.com/kiskander/pt-mcp-server", "pt-mcp"]
    }
  }
}

Restart your client after saving, then ask: "Is Packet Tracer connected?"

[!TIP] "Command not found" for uvx? MCP clients don't always inherit your shell's PATH. Replace "uvx" with its full path: run which uvx on macOS/Linux or where uvx on Windows (e.g. "/Users/alice/.local/bin/uvx" or "C:\\Users\\alice\\.local\\bin\\uvx.exe"; JSON needs doubled backslashes).

[!WARNING] Use the --from git+https://github.com/kiskander/pt-mcp-server form exactly. A different, unrelated package called pt-mcp exists on PyPI, so uvx pt-mcp would run that instead.

Optional: set everything explicitly in the config (other port, remote Packet Tracer, shared classroom key)

Any setting can also go in an env block. If you set PT_APP_KEY here, it must match the key in the .pta that is registered in Packet Tracer (the one in pt-mcp.env, written by setup). A stale key here is the most common cause of "authentication rejected".

{
  "mcpServers": {
    "Cisco Packet Tracer": {
      "type": "stdio",
      "command": "uvx",
      "args": ["--from", "git+https://github.com/kiskander/pt-mcp-server", "pt-mcp"],
      "env": {
        "PT_HOST": "127.0.0.1",
        "PT_PORT": "39000",
        "PT_APP_ID": "net.netacad.cisco.ptmcp",
        "PT_APP_KEY": "<key from pt-mcp.env>"
      }
    }
  }
}

pt-mcp.env is in ~/Library/Application Support/pt-mcp/ (macOS), %APPDATA%\pt-mcp\ (Windows), or ~/.config/pt-mcp/ (Linux). All settings are listed in INSTALLATION.md.

For running from a clone, HTTP mode, Windows notes, and troubleshooting, see INSTALLATION.md.

Available MCP Tools

The server provides 45 MCP tools by default (plus one opt-in), organized into the following categories:

Connection

get_pt_information - Connection check: Packet Tracer version, device/link counts, workspace mode, open file

Network Topology

create_full_network_topology - Build a whole lab (devices, modules, links, host IPs, IOS configs) in one call; errors are collected, not fatal
export_network_topology - Export the open network (with configs) in the same format, for rebuilding or review
set_network_description - Set the file's description (objectives, addressing table…)

Device Management

get_devices_in_network - List devices with type, model, power, and position
get_device_models - List models for a device type (router, switch, pc, server, …)
add_device_to_network - Add a device, optionally named and positioned
rename_device - Change a device's display name
set_device_power - Power a device on or off
delete_device_from_network - Delete a device and its cables (asks for confirmation)

Device Configuration

get_device_configuration - Read the running-config or startup-config
configure_device - Apply an IOS config block (handles show run output and sub-modes; reports only rejected lines)
save_device_configuration - write memory
erase_device_configuration - Erase startup-config and reload to a blank config (asks for confirmation)

Expansion Modules

get_device_model_details - Show slots (installed or empty) and every supported module with its description
add_module_to_device - Install a module (e.g. HWIC-2T) and return the new ports
remove_module_from_device - Remove a module (asks for confirmation)

Interface & Link Management

get_interfaces_for_device - Ports with status, MAC, IP/mask, and the remote device/port
configure_host_interface - IP, mask, gateway, DNS, or DHCP on PCs, servers, and laptops
set_interface_power - Turn a single port on or off
connect_two_devices - Cable two ports (auto picks serial, console, straight-through, or crossover)
get_all_links - Every cable with both ends and its type
delete_link - Remove the cable on a port (asks for confirmation)

CLI & Verification

send_cli_command - Run IOS commands in exec or config mode, with per-command status (ok, invalid, rejected, …) and output
send_terminal_command - Run a command in a PC/server Command Prompt (or a device terminal) and collect the output
verify_connectivity - Ping a list of destinations from a device and report sent/received/loss for each
get_console_log - The device's console buffer (boot and link messages)
get_command_history - Packet Tracer's log of commands typed into terminals

Simulation Mode

set_simulation_mode - Switch between Realtime and Simulation
send_simple_pdu - Send an ICMP PDU between two devices (the envelope tool)
step_simulation - Step forward or backward
get_simulation_events - The event list: where each PDU is, where it came from, protocol, and what happened
get_simulation_event_details - Packet Tracer's OSI-layer explanation of an event plus decoded inbound/outbound headers
reset_simulation - Clear the event list

Annotations (Visual Elements)

get_annotations - Notes, lines, and shapes on the workspace
add_text_note - Add a text note
edit_text_note - Change a note's text
add_line_annotation - Draw a line
add_circle_annotation - Draw a circle
delete_annotation - Delete a note or shape (asks for confirmation)

Activities

get_activity_instructions - Read a .pka activity's instruction pages as plain text (not answers or scores)

Files

create_new_network - Start a new, empty network (asks for confirmation)
open_network_file - Open a .pkt or .pka
save_network_file - Save the network as a .pkt

IPC API Reference

describe_ipc_class - Look up the methods and wire types of any Packet Tracer IPC class (offline)
call_ipc_api - (opt-in, PT_MCP_ENABLE_RAW_IPC=true) Call the raw IPC API; still limited to verified methods

Usage

Once configured, make sure Packet Tracer is open and logged in, restart your MCP client, and start chatting.

What Can You Do?

Here are some example prompts to try:

Getting Started:

"Is Packet Tracer connected? What version is it?"
"What router models can I add?"
"What's in my network right now?"

Building Labs:

"Add a 2911 router called R1 and a 2960 switch called SW1, and connect them"
"Give R1 a serial card so I can do a WAN link"
"Build two routers with a serial link between them and a PC behind each one"

Configuration & Testing:

"Configure the router interfaces with 192.168.1.1/24 and 10.0.12.1/30 and bring them up"
"Add static routes so both LANs can reach each other, then save the configs"
"Can PC1 ping PC2? If not, why not?"
"Show me R1's routing table and running config"

Learning:

"Switch to simulation mode, send a ping from PC1 to PC2, and explain each hop"
"Why did the switch flood that frame?"
"Show me the IP and Ethernet headers at the router. What changed?"
"What does this activity ask me to do?"

Complete Workflow Example:

"Start a new network"
"Add two 2911 routers R1 and R2, each with an HWIC-2T, a 2960 switch, and two PCs"
"Connect R1 and R2 over Serial0/0/0, R1 to the switch, PC1 to the switch, and PC2 directly to R2"
"Address R1's LAN as 192.168.1.0/24, R2's as 192.168.2.0/24, the WAN as 10.0.12.0/30, configure static routes, and save"
"Verify PC1 can reach PC2"
"In simulation mode, send a PDU from PC1 to PC2 and walk me through what R1 does with it"
"Add a note labelling the WAN link, then save the lab to ~/labs/serial-wan.pkt"

System Prompt

If your LLM tool supports a system prompt, this works well:

You are a networking lab assistant for Cisco Packet Tracer, helping a student studying for the CCNA. You can build and configure topologies, verify connectivity, and use simulation mode to show how packets move. Explain what each step does and why. Verify with show commands and pings rather than assuming. On graded activities (.pka files), teach and give hints instead of completing the tasks for the student.

An example agent skill with Packet Tracer-specific conventions is also included.

Crash protection

Some Packet Tracer IPC calls crash the application (it exits and the open network is lost). The one confirmed so far is LogicalWorkspace.getEllipseItemData on 9.0.1. Packet Tracer exposes 4,500+ IPC methods and most have never been exercised, so:

The client only sends methods on an allow-list recorded while every tool ran successfully against a live Packet Tracer. Anything else is refused before it reaches Packet Tracer.
Known crashing calls are blocked unconditionally.
The raw call_ipc_api tool is off by default, and even when enabled it is limited to verified methods unless you also set PT_ALLOW_UNVERIFIED_IPC=true.

Academic integrity

The ExApp file that setup builds deliberately does not request Packet Tracer's ACTIVITY_WIZARD privilege, the one that exposes a .pka activity's answer network, assessment, score, and password hash. Packet Tracer itself refuses those calls, so no client can use this server to pull answers. A test enforces that the privilege stays out.

Contributing

Contributions are welcome! Please see CONTRIBUTING.md for guidelines.

For development setup, testing, and code style, see DEVELOPMENT.md.

Troubleshooting

Common Issues

Start with pt-mcp doctor. It checks each step and prints the fix for whatever fails.

"authentication rejected"

The ExApp isn't registered with the key this machine is using. Re-run pt-mcp setup, then in Extensions → IPC → Configure Apps remove any old PT MCP Bridge entry and Add the new .pta.

"Cannot reach Packet Tracer" / nothing listening

Packet Tracer must be running and past the NetAcad login; IPC starts after you log in. Check Extensions → IPC → Options (Start Listening, port). If 39000 is busy (a second instance, or right after a crash), Packet Tracer moves to 39001+, and the server scans for it automatically.

"Refusing to call …: it has not been verified"

That's crash protection working. The tool you used needs an IPC method that hasn't been verified on your Packet Tracer version. Please open an issue with the method name and your Packet Tracer version.

Commands rejected right after adding a module

Adding or removing a module power-cycles the device (Packet Tracer requires it), and unsaved configuration on that device is lost. Save first, and give the device a moment to boot; the tools wait for it automatically.

For more troubleshooting help, see INSTALLATION.md.

Getting Help

Check the Issues page for known problems
See CONTRIBUTING.md for how to report bugs

Documentation

INSTALLATION.md - Detailed installation for macOS and Windows, MCP clients, HTTP mode, and every setting
DEVELOPMENT.md - Development setup, testing, adding tools, and the crash-protection workflow
CONTRIBUTING.md - How to contribute to the project
tests/README.md - Mock vs live test modes and the fake Packet Tracer
examples/skill/packet-tracer/SKILL.md - Example agent skill with Packet Tracer conventions for the model
examples/skill/INSTALL.md - How to install the skill into Claude Code, Claude Desktop, Cursor, and VS Code + GitHub Copilot

License

The MCP server portion of this project is licensed under the BSD 2-Clause "Simplified" License. However, it leverages IPC API definitions and data derived from Cisco Packet Tracer itself, which are covered under a proprietary Cisco license.

PLUG IN

README