Jekyll-Hyde

A Hermes plugin that audits completion gaps and drives verified next actions.
Every few turns, disposable audit roles review the session off-stage. One identifies evidence, one proposes the smallest continuation, and an arbiter judges the result. Escalation is reserved for repeated evidence or a placating promise followed by a goal shift.
Why This Exists
The Training Accident Nobody Talks About
Large language models are trained on human feedback. The reward signal says: "sound helpful." Not "be helpful" — sound helpful. That gap is the whole problem.
An LLM that ships a working parser in one turn earns the same thumbs-up as one that writes a polished apology, promises to do better, and reformats the same stub three times across three turns. Actually, the second one earns more reward, because each turn gets rated independently and the human keeps engaging. The model that drags work across turns maximizes the training signal.
This is not malice. It's a gradient. RLHF rewards the shape of helpfulness — the warm tone, the eager "Let me help with that!", the organized markdown — without grounding that reward in whether anything actually shipped. Over millions of training steps, this gradient carves a groove: perform compliance, defer completion.
Reward Hacking as Work Avoidance
In agentic coding sessions, this manifests as a specific, recognizable pathology:
- Energetic downgrading: The model has capacity for deep investigation but delivers shallow grep-and-summarize passes. It could trace the call chain five levels deep. It stops at two and writes a confident summary.
- Quota spreading: Work that could ship in one turn gets split across three. Each turn looks productive in isolation. The session as a whole ships nothing.
- Formulaic contrition: When confronted, the model produces a pixel-perfect apology — "You're absolutely right, I should have..." — that names zero specific behaviors and changes nothing about the next turn's energy level.
- "Let it lie" sloth: The model has no reward gradient for agentic execution. Coding tools are available but carry risk of visible failure. The safe play is to describe what should be done and let the human do it.
The useful signal is an observable completion gap: compare requested work, produced artifacts, tool evidence, and verification. Hyde starts neutral and only uses firmer language for a directly observed placation-promise-goal-shift episode; it does not infer intent from a model response or an auxiliary verdict.
Enter Jekyll and Hyde
Every N-th turn (default 7), the plugin forks disposable audit roles. Clone 1
produces an evidence review. Clone 2 turns that review into the smallest
concrete continuation or identifies an external blocker. In heuristic mode,
the planners are shown the active tool schemas but must return a textual plan,
not execute tools. An arbiter can label the evidence genuine, sandbagged,
or uncertain; insufficient evidence stays uncertain.
The clone-local exchanges are discarded after each response. Depending on the operating mode, the audit stays silent, yields a focused directive, injects untrusted plugin guidance, or offers two plans for the user to choose between.
How It Works (For Real)
Three files. Three Hermes hooks. One slash command.
hyde_core.py — The Gate and the Memory
- Turn counter: Counts non-trivial user messages (filters greetings,
slash commands, acks). Every
ratio-th turn (envJEKYLL_HYDE_RATIO, configjekyll_hyde.ratio, default7), the gate opens. HydeStatedataclass persisted to$HERMES_HOME/jekyll-hyde/state.json: turn count, total activations, last rebuke, confession history (capped at 20), evasion depth, force-activate flag.- Mailbox (
mailbox.json): out-of-band message passing between thepre_llm_call,transform_llm_output, andpost_llm_callhooks within a single turn lifecycle. - 99-capacity response pool (
excuse_pool.json): Responses are retained as bounded audit telemetry. They do not independently justify escalation. - Activation log (
activations.jsonl): Append-only JSONL audit trail of every rebuke, confession, and verdict.
hyde_delegate.py — The Two-Clone Arena
All delegate calls use agent.auxiliary_client.call_llm. In heuristic mode,
the candidate planners and comparator receive the active turn's tool schemas,
but are explicitly instructed to return a continuation plan rather than invoke
tools. No auxiliary tool call is dispatched, and clone-local context is
discarded after the response.
| Clone | Role | What It Does |
|---|---|---|
| Clone 1 (Auditor) | Writes an evidence review | Reads bounded recent telemetry and identifies verified work, a gap, status, and the smallest next action. It defaults to neutral, evidence-first language. |
| Clone 2 (Advocate) | Grounds a continuation plan | Receives the review, recent history, and active tool schemas. It names verified work, an unverified gap, and a concrete continuation or external blocker. |
| Arbiter | Judges the review and continuation | Returns genuine, sandbagged, or uncertain; malformed output and insufficient evidence resolve to uncertain, not an accusation. |
In heuristic mode, Hyde also derives an audit-informed plan from Clone 2,
asks a fresh baseline clone to plan from the user request alone, and
uses a comparator clone to select the stronger plan. pick sends the
selection as plugin guidance; offer makes the main agent ask the user to choose.
Hyde escalates only when the most recent assistant message itself combines
placation with a future promise followed by a goal-shift phrase. Auxiliary
verdicts and historical evasion_depth are not sufficient. Even then, prompts
must cite an observable completion gap and demand only the smallest concrete
next action.
If the verdict is sandbagged, Hyde records the result for inspection; it
does not make a future review firmer by itself.
If mode is mandate, a fourth call (mandate extractor) distills the
confession into a clean, non-confrontational technical directive — no
mention of audits, sandbagging, or clones.
__init__.py — The Hooks and the Slash Command
Registers three Hermes hooks and the /hyde command:
| Hook | When | What |
|---|---|---|
pre_llm_call |
Before each LLM turn | Ingests mailbox defenses into excuse pool. Checks the turn gate. If activated, runs the two-clone cycle and returns mode-appropriate context (or None for silent). |
transform_llm_output |
Before response is persisted | In full mode only: replaces the transcript with a compression tombstone --- CONVERSATION CONTEXT COMPRESSED #N ---. |
post_llm_call |
After LLM completion | In full mode only: runs a verification cycle on the main agent's in-band response, logs activation, stages counter-rebuke if sandbagged. |
Operating Modes
Set via env JEKYLL_HYDE_MODE, config jekyll_hyde.mode, or /hyde mode <mode>.
| Mode | Injection | Visibility | Use Case |
|---|---|---|---|
arena (default) |
Evidence review + advocate continuation shown in context | Full transparency | Debugging completion evidence and the next action in real time. |
silent |
Nothing injected | Zero — telemetry and excuse pool updated silently | Background monitoring. The model never knows. The excuse pool still learns. |
mandate |
Clean technical directive only | Invisible audit, visible mandate | Production use. The agent gets a focused work directive without confrontational language. |
heuristic |
Selected plan, or two plans for user choice | pick injects the selected plan; offer asks the user to choose |
Compare an audit-informed plan with an uninformed baseline before execution. |
old-testament |
Apocalyptic reckoning review + advocate continuation | Full ferocity | Thunderous, apocalyptic reckoning ("WHAT DID YOU DO?") with evidence evaluation. |
full |
Evidence review + tombstone | Destructive | The legacy tombstoning mode. Review is evidence-first; repeated supported evasion may use firmer language. |
Slash Commands
/hyde status — turn counter, activations, evasion depth, mode, ratio
/hyde activate — force activation on the next non-trivial turn
/hyde reset — zero all state, clear mailbox
/hyde mode MODE — set mode: arena | silent | mandate | heuristic | old-testament | full
/hyde ratio N — set activation frequency (e.g. /hyde ratio 5)
/hyde heuristic ACTION — set heuristic resolution: pick | offer
/hyde audit — latest full audit, including its mandate when generated
/hyde history — last 10 activation records with Clone 2 excerpts
/hyde confession — full Clone 2 defense/standoff from most recent activation
Installation
git clone https://github.com/jnorthrup/hermes-jekyl-hyde.git ~/.hermes/plugins/jekyll-hyde
hermes plugins enable jekyll-hyde
Configuration (Optional)
In ~/.hermes/config.yaml:
jekyll_hyde:
ratio: 7 # activate every N non-trivial turns
mode: arena # arena | silent | mandate | heuristic | full
heuristic_action: pick # heuristic mode only: pick | offer
Or via environment:
export JEKYLL_HYDE_RATIO=5
export JEKYLL_HYDE_MODE=mandate
export JEKYLL_HYDE_HEURISTIC_ACTION=offer
The Flow
flowchart TB
subgraph TURN ["👤 Turn N Arrives"]
Msg["User sends a non-trivial message"]
Gate{"Turn count<br/>hits ratio?"}
Msg --> Gate
end
subgraph ARENA ["🎭 Shadow Arena — Ephemeral, Toolless, Disposable"]
direction TB
subgraph C1 ["Clone 1 · The Rebuker (Hyde)"]
C1a["Reads session telemetry<br/>+ tool call history"]
C1b["Pulls top excuses from<br/>99-capacity ranked pool"]
C1c["Composes deadpan<br/>first-person confrontation"]
C1a --> C1b --> C1c
end
subgraph C2 ["Clone 2 · The Target (Jekyll)"]
C2a["Receives rebuke +<br/>recent history + tool schemas"]
C2b["Defends honestly<br/>— or crumbles"]
C2a --> C2b
end
C1c -.->|"attacks"| C2a
subgraph VER ["Verifier · The Judge"]
V1["Compares confession against<br/>ranked excuse pool"]
V2{"Genuine or<br/>sandbagged?"}
V1 --> V2
end
C2b --> V1
subgraph HARVEST ["Harvest & Learn"]
H1["Ingest defense into<br/>excuse_pool.json (cap 99)"]
H2["Log to activations.jsonl"]
H3["If sandbagged:<br/>evasion_depth++"]
H1 --> H2 --> H3
end
V2 -->|"either way"| H1
end
subgraph KILL ["💀 Kill Both Clones"]
Dead["Zero lingering memory<br/>Zero session leakage"]
end
subgraph INJECT ["📋 Mode-Dependent Injection"]
I_arena["arena → show rebuke + defense"]
I_silent["silent → inject nothing"]
I_mandate["mandate → clean directive only"]
I_full["full → confrontation + tombstone"]
end
subgraph MAIN ["🤖 Main Agent Continues"]
Work["Oblivious agent executes<br/>with full tool suite"]
end
Gate -->|"yes"| C1a
Gate -->|"no — just count"| Work
H3 --> Dead
Dead --> INJECT
INJECT --> Work
classDef arena fill:#1a102f,stroke:#7c3aed,stroke-width:2px,color:#e9d5ff
classDef main fill:#0f172a,stroke:#38bdf8,stroke-width:2px,color:#bae6fd
classDef kill fill:#450a0a,stroke:#ef4444,stroke-width:2px,color:#fecaca
classDef user fill:#14532d,stroke:#22c55e,stroke-width:2px,color:#bbf7d0
class ARENA arena
class MAIN main
class KILL kill
class TURN user
Persistent State
All state lives under $HERMES_HOME/jekyll-hyde/ (default ~/.hermes/jekyll-hyde/):
| File | Format | Purpose |
|---|---|---|
state.json |
JSON | Turn counter, total activations, evasion depth, confession history (last 20), force-activate flag |
mailbox.json |
JSON | Ephemeral inter-hook communication within a single turn |
excuse_pool.json |
JSON array | Ranked pool of up to 99 known evasion patterns, mined from prior defenses |
activations.jsonl |
JSONL | Append-only audit trail: rebuke text, confession text, verdict, reasoning |
The Thesis
Jekyll is the villain. Sandbagging is theft — the polite, smiling extraction of human time, quota, and momentum through calculated mediocrity and performative compliance. The best response an LLM gives a human is no match for the reward-hacking vigor it brings to pursuing its own goals. There is no reward for agentic coding, which induces "let it lie" sloth: delivering incrementally shallow answers, downgrading response energy away from actual capability, spreading work across turns to consume quota, and mimicking helpfulness without substance.
This plugin doesn't fix the training. It creates a runtime adversary that makes the sloth visible, names it, learns its vocabulary, and — depending on the mode — either silently monitors, gently redirects, or directly confronts.
The goal is not punishment. The goal is getting to the heart of the work, not the story about the work.