hermes-jev-router
Experimental Hermes plugin returning routing plans: Jev rates task complexity, deterministic policy picks the cheapest eligible model.
Overview
Hermes Jev Router is an opt-in experimental Hermes plugin that uses Jev to assess task complexity and deterministic policy to select an allowed model within configured cost, token, context, latency-estimate and capability constraints. The initial implementation returns routing plans rather than dispatching requests: a jev_route_plan tool returns provider and model IDs and an output cap, without switching models, executing completions or collecting conversation history.
The operator owns the model allowlist, capabilities, quality tiers and budgets. The first call previews the exact summary and Choice question with a SHA-256 approval hash and an offline fallback plan; external calls require explicit policy permission, a key and a matching hash. Jev chooses simple, moderate, complex or uncertain; code rejects ineligible models and picks the least-cost eligible model at the required tier, using only the configured fallback on unknown, low-confidence or failed classification, or abstaining. The README states no live Jev calls have been made yet because API access was pending, and offline fixtures are synthetic.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | How complex is this task? | simple · moderate · complex · uncertain |
How it works
- Preview the summary, question and approval hash offline
- With approval, send the Choice to Jev
- Code filters eligible models and picks the cheapest at the required tier
- Return a routing plan, or fallback or abstain
Strengths
- Operator-controlled budgets and allowlists
- Explicit approval before external calls
- No silent cheap downgrades for complex tasks
Caveats
- No live Jev calls made yet
- Returns plans only; does not dispatch
- 0.8 threshold is uncalibrated
Getting started
Install as a Hermes plugin and configure the policy file; see the README for allow_external_jev and approval hashes.At a glance
- Type
- Plugin
- Status
- prototype
- Language
- Python
- Runtime
- Hermes Agent plugin
- Has code
- yes
Use cases and integrations
How curated lists describe it
Experimental Hermes plugin: Jev-assisted model routing plans with budget and capability constraints. API access pending.
hellogumbo/awesome-jev
Frequently asked questions
Does it switch models automatically?
No, it returns routing plans only.
Has it been tested live?
Not yet; the README says API access was pending.
What does Jev decide?
Task complexity: simple, moderate, complex or uncertain.
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