jevcore
Jev decision layer for DeepSeek Harness, MCP hosts and plain Node, offline by default with disclosed egress and opt-in gates.
Overview
jevcore gives an agent TypeSafe Jev's typed judgment surface and nothing more, across three packages. jevcore is the core library with the primitives, providers, egress contract, policy and gates, importing nothing from any harness. jevcore-dsh is a thin DeepSeek Harness plugin exposing one service, three tools and two opt-in gates. jevcore-mcp offers the same three tools (jev_ask, jev_rank, jev_check) over MCP with a stdio binary for other hosts.
Its design principle is offline by default, egress disclosed and nothing default-on. The default provider is an offline mock returning synthetic answers; a live call needs both a live provider setting and a resolved credential. At load it prints its own egress contract, naming each feature that will send data and the field size limits, and notes that redaction is best-effort. Disabled gates register no listeners at all, verified by test; no tool lets the model change gate configuration; and an undecided judge never means allow, defaulting to ask. A safety gate and a context gate are available. It belongs to a family of more than 40 DeepSeek Harness plugins by the same author and is listed on several plugin directories.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Other | Caller-defined judgments via jev_ask, ranking via jev_rank, checks via jev_check | — |
| Yes / no | Is this tool call safe to allow? (opt-in safety gate)(inferred) | — |
How it works
- Install core, DSH plugin or MCP server
- Default mock provider makes no network calls
- Enable live provider and specific features explicitly; contract printed at load
- Gates resolve undecided cases to ask
Strengths
- Offline by default with disclosed egress
- Gates fail safe (undecided means ask)
- Thin adapters over a shared core
Caveats
- Redaction is best-effort
- DSH plugin tracks specific Node versions
At a glance
- Type
- MCP server
- Status
- beta
- Language
- TypeScript
- Runtime
- Node library / DeepSeek Harness plugin / MCP server
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
TypeSafe Jev for DeepSeek Harness, the Model Context Protocol, and plain Node…
wh000wh000/awesome-jev-liveTypeSafe Jev for DeepSeek Harness, the Model Context Protocol, and plain Node: typed judgments instead of prose, offline by default.
hellogumbo/awesome-jevTyped decisions for DeepSeek Harness and any other MCP host, also usable as a plain Node library.
MrJev/awesome-jev
Frequently asked questions
Does it call the network by default?
No, the default provider is an offline mock.
How do I know what data leaves?
It prints an egress contract at load listing each sending feature and size limits.
What happens if Jev cannot decide?
Undecided resolves through config, defaulting to ask rather than allow.
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