jev-mcp-server
PyPI MCP server for Jev with choice, score, noul, compare, verify and batch classify tools plus a one-command client installer.
Overview
jev-mcp-server is a Python MCP server for TypeSafe's Jev that exposes the three official question types (choice, score, noul) plus compare, verify and batch classify. A one-command installer writes the client configuration for Claude Code, Pi, Cursor, OpenCode or Codex.
The README explains Jev as a hosted decision model that returns a typed answer with calibrated probabilities and a confidence, without prose or explanations, and states a single call costs roughly $0.00002 to $0.0001 and returns in about half a second. Choice supports 2-100 options and returns probabilities over all of them so near-ties are visible; score grades on a 2-8 level rubric and returns a fractional index; noul gives a 0-1 degree. A setup tool can verify a key live and store it with restricted permissions instead of placing it in client config.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | Which of these rollout plans is safest? | — |
| Score | Grade risk, severity or quality on an ordered 2-8 level rubric | — |
| Yes / no | Is this change breaking? | yes · no |
| Choice | compare: which of A or B is better? | A · B |
How it works
- Get a TypeSafe API key
- Run uvx jev-mcp-server install for your client
- Restart the client and ask a decision question
- The agent calls a tool and sees the probability split
Strengths
- Installer writes client config automatically
- Near-ties are visible because all option probabilities are returned
- No local model or second LLM required
- Published on PyPI with CI
Caveats
- Hosted dependency on TypeSafe
- Cost and latency figures are the README's own estimates
Getting started
uvx jev-mcp-server install claude-code (or pi, cursor, opencode, codex)At a glance
- Type
- MCP server
- Status
- beta
- Language
- Python
- Runtime
- MCP server (uvx)
- Has code
- yes
- Has tests
- yes
- License
- MIT
Use cases and integrations
How curated lists describe it
MCP server for Jev (TypeSafe System One): the three official question types — choice, score, noul — plus batch classify. Calibrated probabilities, ~0.5s, \<$0.001/call.
logicrw/awesome-jev-projectsMCP server for Jev (TypeSafe System One): the three official question types…
wh000wh000/awesome-jev-liveMCP server for Jev (TypeSafe System One): the three official question types — choice, score, noul — plus batch classify. Calibrated probabilities, ~0.5s, <$0.001/call.
hellogumbo/awesome-jev
Frequently asked questions
Which tools does it expose?
choice, score, noul, compare, verify and batch classify.
How do I install it?
Run uvx jev-mcp-server install followed by your client name.
What does score return?
A fractional index on the rubric, for example 1.88 means between levels 1 and 2, leaning to 2.
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