01What the Hermes Claude Plugin Is and How It Works
The Hermes Claude plugin is an official plugin from Hermes Agent that lets you use Claude SDK with your Claude Code subscription directly inside Hermes. Before this plugin, you could not run Claude inside Hermes Agent at all. Now you can, and you do not need an API key.
The plugin connects Hermes to the Claude app on your computer, not to Anthropic’s API. You already have Claude Code set up locally. Hermes sends a message to the plugin, the plugin starts the Claude CLI, and Claude Opus (or another model) answers.
Hermes then runs the tools it has, like reading files or using the web, and continues the loop until the task is done. This means you get the same powerful brain as Claude, but with Hermes’ tools and memory system, all with one door instead of two.
02Main Features of the Hermes Claude Plugin
The biggest feature is that you no longer need a separate API key and billing to use Claude inside an agent. Your existing Claude Code subscription covers everything. The plugin is super fast and works with any model you prefer, such as Claude Opus 5, Sonnet, Haiku, or Fable.
You can switch models with one line of code. The plugin also connects directly to Hermes Agent OS, so you can use it with all your favorite workflows: Hermes Oracle, Hermes Muse, Hermes Astros, and custom workflows. Hermes keeps its tools, memory profiles, and approval system.
You can also create separate profiles for different models and quickly change between them in the Agent OS chat.
- No API key required
- Works with Claude Opus, Sonnet, Haiku, Fable
- Integrates with all Hermes tools and memory
- One command install
- Super fast response times
03How to Set Up the Hermes Claude Plugin
Setting up the Hermes Claude plugin takes only a few minutes. Make sure you already have Claude Code set up on your computer. Then follow these steps:
- Update Hermes Agent to version 21.4 or newer using the update command in your terminal.
- Install the plugin with one command. The exact command is shown inside the Hermes plugin catalog.
- Create a profile for the Claude model you want to use. For example, run Hermes profile create Claude Opus in your terminal.
- Name the profile something clear, like "Claude Opus."
- Check that the plugin works by sending a test message. You should see a reply like "Yes, it's working."
Once the plugin is installed, your existing Claude Code login handles the rest. You do not need to enter an API key or create a second account.
04How to Use the Hermes Claude Plugin Step by Step
After setup, using the plugin is simple. First, select the profile you created, such as Claude Opus, inside your Hermes Agent OS. Then type your message into the chat.
The plugin starts the Claude CLI in the background. Claude Opus answers, and Hermes calls the tools it needs. For example, you can ask Claude to read a file, run a command, or check its own work.
Hermes handles the tool calls and repeats the loop until the task is done. You can also switch between different Claude models by changing the model name in your profile. In the episode, Julian showed a profile called Claude Opus and then typed "working" to confirm the connection.
The plugin supports all models you have access to in your Claude Code subscription.
05Results and Comparison: Old Way vs. New Way
The episode compared the old way and the new way of using Claude inside an agent. The old way required you to get an API key, add balance to it, and paste that key into Hermes. It took about 20 minutes and created two bills: one for the Claude subscription and another for API usage.
The new way takes about three minutes. You update Hermes, install the plugin, and make a profile. Your existing Claude Code login does the rest.
There is no extra billing because you only use your Claude subscription. The plugin also works much faster. In the episode, Julian tested the plugin and got an instant reply.
The plugin also avoids usage limits that other subscriptions like ChatGPT face. With ChatGPT inside an agent, you run out of tokens quickly. With the Claude plugin, you can keep working without hitting a cap.
06Tips, Limits, and Mistakes to Avoid
When using the Hermes Claude plugin, keep a few things in mind. First, make sure your Hermes Agent is updated to version 21.4 or newer. Older versions will not support the plugin.
Second, only use models you have access to in your Claude Code subscription. Using models like Fable 5 may increase token costs, so be careful if you choose that model. Third, the plugin relies on your existing Claude CLI login.
If you log out, you will need to log in again. Fourth, the plugin does not work if you have not set up Claude Code locally. Finally, avoid using the plugin with the ChatGPT subscription inside the same agent OS, because that might cause confusion.
Stick to one plugin per profile for best results. Always test the connection after setup to confirm everything is working.
07Who Should Use the Hermes Claude Plugin and Why It Matters
The Hermes Claude plugin is for anyone who already uses Hermes Agent and wants to add Claude’s intelligence without extra cost or complexity. It matters because it removes the biggest barrier to using advanced AI agents: the need for an API key and separate billing. Now you can use your Claude subscription directly inside Hermes, with all the tools, memory, and workflows you already have.
This makes Hermes Agent much smarter and more useful. If you run agents overnight, do research, or build custom automation, you will benefit from the speed and power of Claude Opus or other models. The plugin also makes it easy to switch between models so you can match the best brain for each task.
In short, this plugin makes advanced AI agents simpler, cheaper, and faster.
