MCP tools — giving the agent more abilities

✅ Verified 15. 10. 2026Source: official documentation →📋 Copy for your AI

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Many services already speak a language agents understand — your agent just connects. It is called MCP, and it is how you give the agent abilities it does not have on its own: access to your files, to a GitHub project, to your automation tool or to a browser. No code is written for it.

What it is, in plain words

On its own the agent works with a terminal, files and the web. Making it handle everything else would mean a custom solution per service — slow and fragile. MCP is a shared agreement that many services already offer. The agent connects to that ready-made interface and can immediately do what it offers.

What it gives you	Example
The agent can see into your systems	Walks through project files, reads documentation, looks into a database
It drives tools you already use	Creates a card in your automation tool, comments on a task, uploads a file
It can look at the web like a person	Opens a page in a browser and verifies it really looks right
It reaches errors and documentation	Reads reported errors from your monitoring, looks up current library docs

Two kinds of connections

Kind	How it works	Typically for
Local	A program runs on your own server; the agent talks to it inside the machine	Access to folders, a database, a local tool
Remote	The agent connects over the internet to a service; some ask you to sign in	GitHub, project management, error tracking

How to add a connection

From the catalog — the easy route. Selected connections have a catalog and install with one command:
$ hermes mcp catalog $ hermes mcp install
For some connections you pick which tools the agent should see.
By adding an address or command. When a connection is not in the catalog:
$ hermes mcp add
By editing the settings. The manual route, for when you know what you are doing — in ~/.hermes/config.yaml:
mcp_servers: filesystem: command: "npx" args: ["-y", "@modelcontextprotocol/server-filesystem", "/home/user/projects"]

Connections that require a sign-in use hermes mcp login — you log in through the browser, just like any other account. Keys are not written into the settings; a connection reads them from the environment.

Verification: hermes mcp test tells you whether the connection came up and which tools it brought. Changes take effect after the agent restarts.

Safety: a connection is third-party code

⚠️

A connection gives the agent new abilities — and it can do essentially anything it is capable of. Only use sources you trust (the official catalog, verified vendors), and for connections that offer it, limit which tools the agent can see. A connection from an unknown source is like running a stranger's program with access to your server.

Safeguard	What it does
The official catalog	Catalog connections have been reviewed, so it is the safe place to start
Tool selection	You can tick only what you actually want — the agent never even sees the rest
Keys kept out of the file	Secrets come from the environment, not from configuration, so they are not copied into backups or git

When it does not work

Symptom	Cause and what to do
The agent does not see the new tools	The change applies after the agent restarts. Then verify with `hermes mcp test`
The connection reports a sign-in error	Run `hermes mcp login` and sign in through the browser; note that a sign-in does expire
A particular tool is missing	It was left out of the tool selection — `hermes mcp configure` adjusts it
The agent confuses the tools	The connection brought too many tools. Narrow the selection to the ones you use
I do not know what is connected	Ask in the conversation; in the settings it is the `mcp_servers` section

Our tips

Tip	Why
Start with the catalog	Nothing to invent, and you know the connection was reviewed
Add them one at a time	Enabling ten at once hides which one misbehaves and drowns the agent in tools
Narrow the tool selection	Fewer tools means less confusion and less risk of the agent reaching for something you did not intend
Disconnect what you do not use	Every connection is more third-party code on your server

Where next

SecurityWhat the agent may do and what it must ask for⏳ coming soon Scheduled tasksConnections are useful to jobs too Official documentationMCP in detail Community DiscordSee what others connected

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