[BUG] unable to install in Debian / Trixie for hermes

[garyd9]

Description

(using github repo as of 19afb5c)

Following the instructions in docs/hermes-integration.md, unable to install to hermes as "pip install" isn't permitted in newer versions of Debian.

Deviating a bit and stealing a bit of the instructions from docs/getting-started.md, attempted the following before trying the hermes install docs again:

python3 -m venv .venv
source .venv/bin/activate
(then resuming from the hermes doc with: pip install mnemosyne-hermes)

then: hermes config set memory.provider mnemosyne

However, when trying to run "hermes memory setup", there's no mnemosyne option (because "mnemosyne" isn't created in ~/.hermes/plugins/memory )

Environment

• OS: Debian/trixie (debian 13), x64, hermes
• Python version: python 3.11 installed by hermes, system has python 3.13.5
• Mnemosyne version/commit: 19afb5c
• Installation method: (see above)
• Hermes version: Hermes Agent v0.15.1 (2026.5.29), but it's really sync'd to the main branch

Reproduction Steps

All steps shown above in description.

Expected Behavior

That it installs properly?

Actual Behavior

Due to not creating anything in .hermes/plugins/memory, I can't select it as a memory provider.

Mnemosyne Status

Please run the following and paste the output:

hermes mnemosyne stats

n/a - it's not installed.

Checklist

• I have searched existing issues to ensure this is not a duplicate
• I can reproduce this bug consistently
• I have included the full traceback / error message
• I have included my environment details

[garyd9]

The instructions for the hermes install should include creating the virtual environment for linux-based installs. Then, I think there might be a command missing after the "pip install mnemosyne-hermes." Something like "python -m pip mnemosyne.install", but that's just a guess. :)

Also, debian systems likely won't have a python3-venv package installed by default, so "python3 -m venv .venv" will also fail. That can be handled by either installing venv (sudo apt install python3-venv -y), or using "uv" instead (uv venv .venv)

[AxDSan]

Hey @garyd9 — thanks for reporting this.

Debian Trixie enforces PEP 668, which blocks global pip installs. If you're using Hermes with a venv (which is the recommended setup for Trixie/Ubuntu 24.04+), try:

1. Activate your Hermes venv: source ~/.hermes/venv/bin/activate
2. Run install inside it: pip install mnemosyne
3. Then hermes memory setup should find the provider

The docs currently assume pip works globally — I'll update docs/hermes-integration.md this week to cover PEP 668 and venv-based installs.

If you're still stuck after the venv approach, can you share the output of hermes memory setup --debug?

[garyd9]

That would have been too easy. ;)

1. Activate your Hermes venv: source ~/.hermes/venv/bin/activate

xx@hermes:~$ source ~/.hermes/venv/bin/activate
-bash: /home/xx/.hermes/venv/bin/activate: No such file or directory

ls -l ~/.hermes/venv
ls: cannot access '/home/xx/.hermes/venv': No such file or directory

... did you mean ~/.hermes/hermes-agent/venv ?

[AxDSan]

@garyd9 sorry for the wait on this. You ran into two things at once and neither is your fault.

First, Debian 13 blocks raw pip installs by default, which the docs don't mention. You found the right workaround with a venv.

Second, even after installing in the venv, Hermes doesn't automatically discover the plugin. It scans a specific folder on disk for plugins and doesn't know to look at what pip installed. That's an integration gap I'm fixing now.

Quick workaround:

mkdir -p ~/.hermes/plugins/memory/mnemosyne
ln -s ~/.hermes/hermes-agent/venv/lib/python*/site-packages/mnemosyne_hermes/* ~/.hermes/plugins/memory/mnemosyne/
hermes gateway restart

I'm updating the install docs to cover the Debian case and adding the symlink step so next person through doesn't hit this. Thanks for the detailed report - really helps to know exactly where the docs fall short.

[garyd9]

This isn't working. The symbolic link command actually leaves a fie named '*' that is an invalid link. Even if I correct the link command to "ln -s ~/.hermes/hermes-agent/venv/lib/python3.11/site-packages/mnemosyne /.hermes/plugins/memory/", the plugin still isn't available after running "hermes gateway restart." There's a missing step.

I'm going to put this aside for now and just go back to using hindsight. I'm sure you'll work all this out eventually.

[AxDSan]

@garyd9 sorry this was such a rough ride. You hit the exact intersection of three issues (PEP 668, namespace shadowing, and the missing plugin symlink step) that we've since been fixing in batch.

The short version: the install process has been completely reworked across #253 (symlink naming fix), #233/#212 (namespace shadowing), and the Hermes plugin itself. Debian Trixie installs should work cleanly once the next release ships. Your report directly drove those fixes.

Closing this for now since the root causes are being addressed. If the next release still doesn't work for you, please reopen.