jevex
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@jevexwhere is session expiry actually enforced?"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
jevex
One MCP tool that returns the files a coding agent should read.
Ask where is this actually enforced? TypeSafe Jev scores a shortlist. The agent reads those lines instead of grepping the tree. Not a second agent. Not a jev_evaluate wrapper.

Illustration, not a screen recording.
agy + Gemini 3.8 Flash · n=16 SWE-bench Verified · 1200s cap: 160s → 69s, $8.74 → $3.13. Patch file 16/16 both arms.
Fixture packet (toy session.py, not the SWE run) — examples/session-expiry.json:
{
"source_of_truth": [{
"path": "src/auth/session.py",
"symbol": "assert_session_fresh",
"range": [32, 35]
}],
"status": "sufficient"
}You still plan and patch. jevex only answers what to read.
Numbers
Same cheap agent both arms.
without jevex | with jevex | |
Mean time | 160s | 69s |
Agent bill | $8.74 | $3.13 |
Hit the file to patch | 16 / 16 | 16 / 16 |
Jev | — | ~$0.0015 / question |
Under a 90s cap the without-arm mostly returned empty JSON (timeout): 1/16 vs 11/16 finished. Separate Claude Code fixture, n=5: 6.8 files → 2.2.
Related: OpenJev, Aider's repo map, Serena, the agent's own grep. jevex is index-then-ask for any MCP agent.
Related MCP server: codegraph-mcp
How it works
Index whatever a coding agent can already read (py, ts, go, rs, md, …).
Ask
codebase_investigate.Jev ranks a shortlist. The agent
Reads those ranges.
you → coding agent → codebase_investigate → Jev on a shortlist → files + lines → agent readsIntegration
Needs a TypeSafe JEV_API_KEY.
git clone https://github.com/jimmyhealer/jevex
cd jevex
pip install -e ".[mcp]"claude mcp add jevex \
-e JEV_API_KEY=ts_... \
-e JEV_EXPLORER_REPO=/absolute/path/to/your/repo \
-- jevex-mcpAsk: where is session expiry enforced? It should call codebase_investigate first.
CLI
cd /path/to/your/repo
jevex investigate "Where is session expiry actually enforced?"--json prints the full packet. --no-jev is a lexical ablation (no key, not the product).
Limits
Read-only. Not a patcher. Jev never sees the whole repo — only the shortlist.
MIT. CONTRIBUTING.md · SECURITY.md
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