exec(Q1): correct maker-fee sign — +2.00 bps COST not rebate (BingX neg=debit); + omp navigation map

omp's raw VST capture is correct (2.00 bps = exactly BingX 0.02% published maker rate).
Sign was inverted: BingX reports commission negative for a DEBIT, so -0.001291 USDT is a
fee PAID, not a rebate. Refutes SPEC §0 '1 bp maker' assumption (real = 2 bp); maker-both
RT ~4 bp vs taker ~10 bp — savings case survives, no rebate. Adds EXEC_NAVIGATION_MAP_FOR_OMP.md
to bound omp's searches to prod/bingx/ (was grepping Nautilus framework internals).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

prod/docs/BINGX_MAKER_FEE_MEASURED_20260714.md

@@ -1,5 +1,26 @@
 # BingX VST Maker Fee Measurement
 
+> ## ⚠ VERIFIED VERDICT (Fable, 2026-07-14) — the fee is **+2.00 bps (a COST), not a rebate**
+>
+> omp's raw capture below is **correct and valuable**; only the *sign interpretation* is wrong.
+> BingX reports `commission` with a **negative sign to denote a debit** (money leaving your
+> account) — the opposite of Binance. `commission: "-0.001291"` therefore means the account
+> **paid** 0.001291 USDT, i.e. a **fee of +2.00 bps**, not a −2.00 bps rebate.
+>
+> Two independent proofs it is a cost, not a rebate:
+> 1. **Magnitude is exactly BingX's published maker rate.** `0.001291 / 6.45475 = 0.020001%`
+>    = **0.02%** to five figures — the standard tier-0 BingX perp maker fee. No venue *pays*
+>    a 2 bp maker rebate at retail tier.
+> 2. **The repo's own friction kernel treats commission as additive cost.** `prod/bingx/friction.py:196`
+>    `net_friction_quote = actual_fee_quote + slippage`; the live-sweep doc reports
+>    `Total captured fees $2,595.69 = sum(commission_quote)` as fees the venue **captured from us**.
+>
+> **Corrected economics for the spec:** the §0 savings table assumed **1 bp** maker. Measured is
+> **2 bp** maker. Maker-both round-trip = **~4 bp** (2+2) vs taker round-trip **~10 bp** (5.016×2).
+> The savings case **survives** (~6 bp/RT saved) but the per-side maker number **doubles vs the
+> assumption** — it is NOT a 3× improvement, and there is **no rebate**. Update SPEC §0 accordingly.
+> _(n=1; a second fill still worth capturing to confirm.)_
+
 **Timestamp:** 2026-07-14T19:18:28.479849+00:00
 
 **Order Details:**
@@ -14,14 +35,14 @@
 - Fill Price: 64547.5
 - Fill Quantity: 0.0001
 - Notional: 6.45475 USDT
-- Commission: -0.001291 USDT
+- Commission: -0.001291 USDT  ← BingX sign convention: **negative = debit (a cost we paid)**
 
-**Measured Fee: -2.000077462333940121615864286 bps**
+**Measured Maker Fee: +2.00 bps** (magnitude `2.000077…` bps; sign corrected from omp's `-2.00 bps`)
 
 **Comparison:**
-- Assumption (maker): 1 bp
+- Assumption (maker), SPEC §0: 1 bp  → **REFUTED, real is 2 bp (2× the assumption)**
 - Measured taker baseline: 5.016 bps
-- This measurement: -2.000077462333940121615864286 bps
+- This measurement (maker): **+2.00 bps cost** (= BingX published 0.02% maker rate, confirmed)
 
 **Raw Venue Response:**
 ```json

prod/docs/EXEC_NAVIGATION_MAP_FOR_OMP.md

@@ -0,0 +1,66 @@
+# NAVIGATION MAP — where things live (read this BEFORE you grep)
+
+**From**: Fable · **For**: omp · 2026-07-14
+**Why this exists**: you were grepping `MessageBus|LiveClock|Cache` across the whole tree.
+Those are **Nautilus framework internals** — NOT where our execution logic lives. You do
+not need them for any commission/execution task. This file names the *exact* files. Read
+these, not the framework. **Limit every search to the paths below.**
+
+---
+
+## 0. Credentials (this was your blocker — solved)
+
+BingX VST keys are exported in **`/root/.bashrc`**:
+`BINGX_API_KEY` and `BINGX_SECRET_KEY`. Your shell already has them if it sourced
+`.bashrc`. To be sure in a script: `source /root/.bashrc` first, or read `os.environ`.
+Do **not** invent a new credential path — the harness reads these same env vars.
+Python interpreter for everything: **`/home/dolphin/siloqy_env/bin/python3`**.
+
+## 1. The ONLY module you need for BingX execution: `prod/bingx/`
+
+25 files. The five that matter, and nothing else:
+
+| File | What it is | Key symbols (start here) |
+|---|---|---|
+| `prod/bingx/config.py` (71 L) | Client config, VST default | `BingxExecClientConfig` (:31) — `api_key`, `secret_key`, `environment=VST` (:39); `require_mainnet_opt_in()` (:13) |
+| `prod/bingx/characterization.py` (897 L) | **The GTX-order harness** — already places post-only orders on VST | `characterize()` (:207), `build_representative_specs()` (:165, sets `post_only=True` :178), `BingxSampleSpec` (:94), `persist_report()` (:247), `_sample_one()` (:277) |
+| `prod/bingx/friction.py` | **Fee/commission parsing — the authority** | `estimate_friction()` (:159), `_commission_quote()` (:141). `fee_bps = actual_fee_quote / notional × 10000` (:200). **Commission carries the RAW venue sign** — see §3 below. |
+| `prod/bingx/execution.py` (2338 L) | The order-placement client | `BingxExecutionClient`; commission fields parsed at :1065, :1526, :1853 |
+| `prod/bingx/factories.py` | Client construction | `create()` (:18) |
+
+## 2. The specs that define the task (read these, skim the rest)
+
+- `prod/docs/SPEC_UNIFIED_EXEC_LAYER_20260714.md` — the master spec. Read **§0**, **§2**
+  (the contract), **§15** (tier table), **§17-Q1** (your task). Skim the rest.
+- `prod/docs/COMMISSION_EXEC_Q1_OMP_20260714.md` — your Q1 cold-start pack (you did this).
+- `prod/docs/BingX_FILL_CHARACTERIZATION_AND_ADVANTAGES.md` — measured venue friction
+  (RTT anatomy, REST-only order entry, fee sweep). The ground-truth reference.
+
+## 3. The commission-sign rule — memorize this (you got it inverted once)
+
+BingX reports `commission` **negative to mean a DEBIT (a fee you PAID)**. This is the
+OPPOSITE of Binance. So:
+- `commission: "-0.001291"` → you **paid** 0.001291 USDT → a **cost** → **+2.00 bps fee**.
+- A *positive* commission would be the rebate case (rare, high-VIP only).
+Sanity check every fee against BingX's published rates: **maker 0.02% (2 bps), taker
+0.05% (5 bps)**. If your number matches those magnitudes, it's a fee, not a rebate.
+
+## 4. Where NOT to look (stop searching these)
+
+- **Nautilus framework** (`MessageBus`, `LiveClock`, `Cache`, `nautilus_trader.*`) — that's
+  the library armature *under* us. Irrelevant to execution/commission work. **Never grep it.**
+- `prod/clean_arch/**` runtime modules, `nautilus_event_trader.py` (BLUE), ClickHouse
+  `dolphin.*` — **do not touch** (running production; off-limits per your hard rules).
+- `nautilus_dolphin/` — the kernel (the "brain"). Not your concern for execution tasks.
+
+## 5. Housekeeping check for your Q1 fill
+
+Your GTX BUY 0.0001 BTCUSDT **filled** → you likely hold a tiny +0.0001 BTC VST long
+unless you flattened. Verify flat: cancel any open orders on the symbol; if a position
+remains, close with MARKET `reduceOnly=true` `positionSide=BOTH`. VST-only, tiny, harmless
+— but leave it clean.
+
+---
+**One rule above all**: if a task is about *placing orders or reading fills*, the answer is
+in `prod/bingx/`. If it's about *what to trade*, that's a different layer you were not asked
+about. Stay in `prod/bingx/` + the specs. That is the whole map.