plan: general gated execution — unlimited actions, gated by risk classifier
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Evaluate the agent's action path against the OIKOS.md design. Finding: the
intended model (unlimited runbook-driven actions gated by a risk classifier)
already exists on paper and in scaffolding, but the live agent path regressed
to a hard-coded 5-action enum that bypasses the classifier. Plan a layered
realignment: (0) one general gated `run` primitive, (1) runbooks-as-data as the
reliable fast-path, (2) learning. Chosen v1 posture: approve-most (read-only
auto-runs, all state changes gate). Incremental, each step shippable.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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# 2026-07-10 — General gated execution: from fixed actions to unlimited-but-gated
**Status:** Planned
## Goal
Make Nomos able to do **anything** needed to maintain the homelab — provision
LXCs, deploy services, debug, restart, fix configs, investigate — without that
capability being a fixed enum of hand-coded actions. The action space is
unlimited; the *gate* on it is a risk classifier + operator approval, not a
whitelist of tricks. Knowledge (the graph + runbooks) supplies the *how*; the
agent's reasoning supplies the *what*; the classifier supplies the *may I*.
Operator directive (2026-07-10): **"The number of actions the agent should be
able to do is unlimited. We need logic to gate destructive actions, but we
should not limit what the agent can do."**
Chosen autonomy posture for v1: **approve-most (cautious)** — only genuinely
read-only commands auto-run; anything that changes state requires operator
approval. We can relax later once the classifier and ledger have earned trust.
## This is a realignment, not a new idea
[.agents/OIKOS.md](../.agents/OIKOS.md) already specifies this exact model:
> The classifier scores **risk class × blast radius × confidence** and routes:
> auto-act / escalate / queue. The classifier can only *lower* autonomy relative
> to policy, never raise it. When in doubt, escalate.
> Act — execute through `homelab` commands or **runbooks** (never ad-hoc SSH).
So the target architecture is the *documented* architecture. The problem is the
implementation diverged from it on the agent's action path.
## Gap analysis (grounded in code)
| Designed (OIKOS.md) | Actually implemented today |
|---|---|
| Classifier routes every action by risk × blast × confidence | [`internal/policy/classify.go`](../internal/policy/classify.go) `ClassifySignal()` only classifies **Signals** (the Observe pipeline), by entity+action-type. It is **not** called by the agent's mutation path. |
| Agent acts through unlimited **runbooks** | Agent acts through `request_execution` with a **hard-coded enum**: `restart, systemctl, pct_exec, apt_upgrade, pct_create` ([`internal/mcp/server.go`](../internal/mcp/server.go)), each bespoke Go, gated by per-action `if`s, not the classifier. New capability = new Go + redeploy. |
| Runbooks/skills are executable data | `skills` table + `.agents/skills/*` + `knowledge_entities` exist and are *readable* (`get_skills`), but **nothing executes a runbook**. The knowledge is inert w.r.t. action. |
| Auto-act loop consumes classified signals and acts | [`internal/actuator/actuator.go:124`](../internal/actuator/actuator.go) is a literal `"stub execution"` — it marks work done without doing it. |
| "Never ad-hoc SSH" | `pct_exec` **is** ad-hoc SSH (arbitrary shell in a container) and **auto-runs with no approval or classification**. |
Net: the elegant model exists as scaffolding (classifier, policy schema, risk
classes, blast-radius graph walks, skills-as-data, ledger, and the
approval+feedback plumbing hardened in the 2026-07-09/10 sessions), but the live
agent→action path is a bag of tricks that bypasses all of it. Everything added
in the recent LXC-deploy work (`pct_create` + DNS/VMID/template logic) made the
bag *bigger* — reliable, but on the wrong axis.
**Bones that already exist and get reused:** `internal/policy` (classifier +
`computeBlastRadius`/`blast_radius()` SQL), `risk_classes`/`action_risk` tables,
`seeds/policy.yaml`, `executions`/`approvals`/`audit_log`, the MCP SSH machinery,
and the inline approval + execution-status feedback loop (chat polls
`GET /executions/{id}`).
## Target architecture — three layers
### Layer 0 — one general gated primitive (the foundation)
Collapse the fixed enum into essentially one tool:
```
run(target, command, purpose, [declared_risk])
```
- `target` — any host or LXC slug; resolves to SSH (host) or `pct exec` (LXC).
- `command` — arbitrary shell.
- `purpose` — the agent's stated intent (shown to the operator, feeds classify).
- `declared_risk` — optional agent self-assessment.
Every call flows through:
1. **Classify** the command → `read_only | reversible_low | config_mutation |
destructive`. Rule-based:
- read-only **allowlist** (e.g. leading verb in `cat, ls, stat, journalctl,
systemctl status|is-active, pct config|status, df, free, uptime, ip, ss,
docker ps|logs, git status|log`) → `read_only`;
- destructive **denylist** (`rm -rf`, `dd`, `mkfs`, `wipefs`, `pct destroy`,
`qm destroy`, `shutdown`, `reboot`, `> /dev/`, `:(){ :|:& };:`, secret
exfiltration, piping remote scripts to a root shell) → `destructive`;
- anything writing state / installing / editing configs → `config_mutation`;
- **default → escalate** (`config_mutation`) when unsure.
The classifier may only make `declared_risk` **stricter**, never looser
(mirrors "can only lower autonomy, never raise").
2. **Route** (approve-most posture):
- `read_only` → auto-run + ledger, no approval.
- `reversible_low` / `config_mutation` → **operator approval** (v1 gates all
state changes; a later posture can auto-run `reversible_low`).
- `destructive` → approval **+ typed confirmation phrase**.
3. **Execute** (existing SSH/`pct exec`), **verify** (optional check command),
**ledger** (`executions` + `audit_log`), **stream feedback to chat** (reuse
the `GET /executions/{id}` polling + `InlineApproval` phases already built).
Layer 0 alone delivers "the agent can attempt anything; state changes are gated."
### Layer 1 — runbooks as executable data (reliability without rigidity)
The hard-won procedures become **runbooks in the knowledge DB**, retrieved and
executed step-by-step via Layer 0 — not frozen Go:
- `pct_create` + its DNS-self-heal / VMID-collision / template-resolution /
locale logic becomes the canonical **"provision LXC" runbook** (parametric
steps the agent fills in and runs through `run`). The reliability survives as
documented, reusable steps rather than a compiled handler.
- New capability = **new runbook (data)**, no redeploy.
- Keep a *small* set of mechanical helpers where a shell step is genuinely
fiddly (e.g. "pick a free cluster VMID"), exposed as callable sub-tools — but
the flow is agent-driven, not enum-driven.
This is the crucial **both/and**: the general primitive is the unlimited escape
hatch; curated runbooks are the reliable fast-path so the agent doesn't
re-derive DNS/VMID/docker every time (the exact thing that failed repeatedly in
the 2026-07-09 sessions).
### Layer 2 — learning closes the loop
Successful ad-hoc `run` sequences get promoted into runbooks/patterns (the
`learning` engine + `skills` table already exist for this); the failure ledger
informs retries. The system grows more capable **as data**, not as code.
## Safety model (the whole point of the gate)
- **Default-escalate.** Nothing is *forbidden*; risky things need the operator's
"yes." Unknown/unparseable risk → approval.
- **Hard denylist** for catastrophic patterns → always typed confirmation, even
if the agent declared them safe.
- **Blast radius at approval time** — graph walk (`blast_radius()` exists):
"this restarts caddy → 8 downstream services."
- **Preview / dry-run** where the command supports it.
- **Kill-switch** (`global.auto_act`, per-target `never_auto_act.*`) already
exists; extend to a global "require approval for everything" flip.
- **Full audit ledger** — every command, its classification, decision, actor,
output. Non-negotiable.
- **Scope guards** — resolve `target` to a real entity first; refuse commands
against `destroyed`/unknown targets; cap output size (already done).
## Honest risks / tradeoffs
- Trades a small vetted surface (5 actions) for arbitrary root across the fleet,
LLM-driven, gated only by classifier + approval. Classifying arbitrary shell
perfectly is impossible; **default-escalate + hard denylist + always-on audit**
is the mitigation, not perfect classification.
- Approve-most means more operator clicks initially. Acceptable while trust is
built; the posture is a config knob, not a rewrite.
- Runbook-as-data can drift from reality like any doc; the ledger + verify step
+ learning loop are the correction mechanism.
## Migration path (incremental, each step shippable)
1. **Command classifier** — extend `internal/policy` with
`ClassifyCommand(cmd, declaredRisk) → riskClass` (allowlist/denylist/default-
escalate + can-only-escalate rule). Unit-tested against a corpus of safe /
mutating / catastrophic commands.
2. **`run` tool** — new MCP tool routing classify → gate → execute → the
existing feedback path. Ship alongside the current tools (no removal yet).
3. **Approval context** — surface risk class + blast radius + purpose on the
approval (chat `InlineApproval` + Ops page); typed-confirmation for
destructive.
4. **Runbook execution** — a "provision LXC" runbook (ports the current
`pct_create` logic) executed via `run`; validate parity with today's handler.
5. **Retire the enum** — convert remaining hard-coded actions to runbooks; make
`request_execution` a thin deprecated alias or remove it.
6. **Revive auto-act** — replace the actuator stub, reusing the *same* classifier
for the Observe→Act direction (signals), still approve-most.
## Verification
- Classifier corpus test: read-only commands auto-pass; a set of known
catastrophic commands always route to destructive+confirmation; ambiguous
commands escalate. No command auto-runs that mutates state.
- End-to-end: operator asks Nomos a novel task **not** in the old enum (e.g.
"tail caddy's error log and restart it if it's flapping"); Nomos composes
`run` calls; read-only steps auto-run, the restart gates for approval; chat
shows live status; ledger records each command + classification.
- Parity: "provision an LXC with a service" via the runbook path matches the
reliability proven for the `pct_create` handler (free VMID, DNS, install,
verify), then destroy.
## Open questions for the operator
- **Reversible-low posture:** keep gating restarts/syncs in v1 (chosen), or
auto-run them once the classifier is trusted?
- **Confirmation phrase:** per-action typed phrase for destructive, or a global
one?
- **Runbook authorship:** operator-authored only, or may Nomos propose new
runbooks (subject to approval) from successful ad-hoc sequences?
- **Blast-radius threshold:** should a large blast radius force approval even for
otherwise-reversible actions?

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| 2026-07-08 | [Liveness, drift, and UX cohesion](2026-07-08-liveness-drift-and-ux-cohesion.md) | In Progress |
| 2026-07-09 | [Chat sessions: reliability, cost, and session-management fixes](2026-07-09-chat-sessions-improvements.md) | Planned |
| 2026-07-09 | [Session execution, UX, and learning improvements](2026-07-09-session-execution-and-ux-fixes.md) | Planned |
| 2026-07-10 | [General gated execution: unlimited actions, gated by risk](2026-07-10-general-gated-execution.md) | Planned |
## Done