Hermes Agent plugin: replace em dashes with appropriate punctuation using structural heuristics

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BarnacleBoy fa01b7a6f0 fix: register transform_llm_output hook as fallback Adds a real hook registration so em dashes are caught even when the barnacleboy-output wrapper plugin fails to load or import this module. The barnacleboy-output plugin is still the PRIMARY transform owner - it chains em-dash-sub + spongebob-vocab + safety-net. This registration is a fallback that fires independently. Both hooks run on every turn. The turn_finalizer uses the first non-None result, so barnacleboy-output's chained transform wins when healthy.		2026-09-14 15:34:41 +00:00
.gitignore	chore: add .gitignore, remove __pycache__ from tracking	2026-08-10 14:11:18 +00:00
__init__.py	fix: register transform_llm_output hook as fallback	2026-09-14 15:34:41 +00:00
plugin.yaml	Initial commit: em-dash-sub Hermes plugin	2026-08-10 14:10:47 +00:00
README.md	docs: add debugging instructions and multiple plugin coexistence docs	2026-08-26 15:25:03 +00:00
test_integration.py	feat: add comma substitution, paired dash detection, and conjunction handling	2026-08-25 12:56:36 +00:00
test_new_features.py	feat: add comma substitution, paired dash detection, and conjunction handling	2026-08-25 12:56:36 +00:00
test_plugin.py	feat: add comma substitution, paired dash detection, and conjunction handling	2026-08-25 12:56:36 +00:00

README.md

Em Dash Sub

A Hermes Agent plugin that replaces em dashes (—) with typographically appropriate punctuation.

Uses the transform_llm_output hook — zero inference tokens, pure regex post-processing.

How it works

Three-pass substitution:

Paired em dashes — Detects — text — patterns and wraps them:
- Non-restrictive clauses (starting with which, who, that, where, when) → , commas,
- Removable asides and appositives → (parentheses)
Single em dashes — Heuristic substitution based on the word that follows:
- Coordinating conjunction (but, yet, so, nor) → ,
- Weak starter (that, which, who, whom, whose, where, when) → ,
- Contrasting clause (pronoun or auxiliary verb follows) → ;
- Explanation (article, preposition, or infinitive follows) → :
- Everything else → : (safe default)
Whitespace hygiene — Cleans up double spaces, leading punctuation, and spacing around parens.

Code blocks, inline code, URLs, and file paths are preserved.

Installation

git clone https://git.jezzahehn.com/KrustyPlanet/em-dash-sub.git ~/.hermes/plugins/em-dash-sub
hermes plugins enable em-dash-sub

Requires a /reset or gateway restart.

Configuration

Env var	Effect
`EM_DASH_SUB_DISABLED=1`	Disable the plugin
`EM_DASH_PREFER_SEMICOLON=1`	Use semicolons for all single em dashes (skip heuristic)

Debugging

The plugin logs at INFO level when it fires:

em-dash-sub: no em dash found in text — text has no em dashes, passes through
em-dash-sub: transforming N chars with em dashes — em dashes found and replaced

Check logs with:

grep "em-dash-sub" ~/.hermes/logs/agent.log

Stale .pyc files: If the plugin stops working after a code change, the gateway process may be holding a stale .pyc in memory. Restart the gateway:

sudo systemctl restart hermes-gateway

Multiple Plugin Coexistence

The transform_llm_output hook uses a "first non-empty string wins" approach. Multiple plugins can register for the same hook; the first callback to return a non-None string is used as the final response.

This plugin is registered before spongebob-vocab, so it takes priority when em dashes are detected. When no em dashes are present, it returns None and the next plugin's output is used.

Examples

Before	After
The key insight — it's all about scale.	The key insight: it's all about scale.
My mentor — a seasoned developer — disagreed.	My mentor (a seasoned developer) disagreed.
The system — which handles 10K requests — crashed.	The system, which handles 10K requests, crashed.
I thought it was working — it wasn't.	I thought it was working; it wasn't.
Three things — speed, cost, reliability.	Three things: speed, cost, reliability.
It was hard — but we did it.	It was hard, but we did it.
The theory — that morality is pluralistic — is influential.	The theory, that morality is pluralistic, is influential.

License

MIT