Question 1

Does that -60% figure mean I will actually save Codex quota?

Accepted Answer

No. The README calls it a historical simulation of about -60% against full Astra on 237 turns under the old policy, and says explicitly that it is neither measured Codex quota saved nor evidence for the current policy. Protocol and limitations are written up in BACKTEST.md, and Terra attempts still count as native in reports.

Question 2

What happens if Jev is down or rate-limits me in the middle of a turn?

Accepted Answer

The turn survives. Any Jev error keeps the call alive on a separately logged technical fail-open route, Astra at medium. A sentinel file routes without Jev instantly, and there is no low-confidence fallback to Sol, no keyword-to-model rule, and no target distribution.

Question 3

Does Jev see my whole conversation, and does the router change how Codex handles tools?

Accepted Answer

Two independent projections. Jev only sees a bounded decision state; the executing model receives the complete canonical replay Codex holds, including instructions, compaction handoff, tool calls and tool results. The Responses SSE stream is relayed verbatim with no format conversion, so tool calls, reasoning and compaction behave natively.

Question 4

Can it silently start spending money on another provider?

Accepted Answer

Not on healthy turns: provider discovery is not even run while the native ChatGPT allowance answers. While dry it derives at most two candidates from routes this machine already has configured, filtered and cached locally for 30 seconds, always excluding jev/auto to prevent recursion, and the decided thinking depth travels with the substituted call.

Question 5

What are the four questions Jev answers per call?

Accepted Answer

In one request Jev decides whether the call falls under the mandatory-Astra policy, the least expensive sufficient capability tier among Luna, Terra, Sol and Astra, the minimum sufficient thinking depth from low to max, and a bounded route lease of one_call, tool_chain or user_turn.

Question 6

What does the route lease control?

Accepted Answer

It bounds how long the decision is reused: one_call for a single call, tool_chain to cover continuations after tools, or user_turn until the next real user message. Routing happens per model call, including continuations, so a task never switches tier mid-chain.

Question 7

Where are routing decisions recorded?

Accepted Answer

Every routed turn is logged locally to ~/.codex/codex-router/jev-router-live.jsonl for calibration, and the log is never published. Jev's combined confidence and all four choice distributions are logged separately.

Jev Codex Router

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