eos-mcp

MCP server for Arista EOS device operations via eAPI.

Exposes EOS show commands, running-config retrieval, configuration push (via configure session with commit timer), and tech-support collection to MCP-compatible AI assistants.

Installation

pip install eos-mcp

Configuration

Copy config.ini.example to ~/.config/eos-mcp/config.ini and fill in credentials:

[DEFAULT]
username = admin
password = yourpassword
transport = https
verify = false

[switch1.example.com]
tags = main,dc1

[switch2.example.com]
tags = main,dc1

Config file discovery order:

1. EOS_MCP_CONFIG environment variable
2. ./config.ini (current directory)
3. ~/.config/eos-mcp/config.ini

(Individual MCP tool calls may also override the path via a config_path parameter.)

Usage

# Verify config and list devices
eos-mcp --check

# Test connectivity to a specific host
eos-mcp --check --check-host switch1.example.com

# Start MCP server (stdio transport)
eos-mcp

Tools

Development

Live smoke test

Unit tests check logic against fixtures; they cannot tell you that a tool has stopped returning real data. scripts/smoke_test.py runs every registered tool against the configured devices and fails on empty, malformed or error answers:

# uses the same inventory file as the server (EOS_MCP_CONFIG)
uv run python scripts/smoke_test.py
uv run python scripts/smoke_test.py --only facts --traceback

• Read-only. push_config, confirm_config_session and abort_config_session are skipped by name, and a test enforces that. collect_tech_support is skipped too — it changes nothing, but it is minutes of device CPU for an answer no assertion would read. The command-running tools are exercised with show version: they accept enable-mode commands in general, and a smoke test must not be the thing that types one that matters.
• No payloads in the report. Tool names and statuses only; error text is redacted too, since every error here is prefixed with the device it came from and the payloads are configuration.
• Nothing estate-specific in the specs. The device the per-host tools need is discovered at run time from the configured inventory, and skipped when it is empty. Two tests keep it that way: one refuses those parameters as literals, the other bans anything address-shaped anywhere in the file, because this repository is public.
• Every probe refuses the Error (<host>): ... line these tools return in place of raising — otherwise an unreachable device would read as a successful call.
• CI enforces the cheap half: a tool registered without a probe spec fails the build (tests/test_smoke_probes.py), so adding a tool forces the question "how would we know it works?".
• scripts/smoke_harness.py is the engine and holds no EOS knowledge: it is kept identical across the servers that share it, so fix engine bugs once and sync the file rather than patching this copy.

Requirements

• Python >= 3.10
• Arista EOS with eAPI enabled (management api http-commands)
• Network access to port 443 (HTTPS) on target devices

License

Apache-2.0