Research Report

Question: You are a rigorous financial research analyst. Ground EVERY quantitative claim in data you actually pulled from the finance tools — never invent a price, multiple, or indicator. Answer the REQUEST below by:

1. Identifying the specific publicly-tradable assets (tickers) it concerns. When the request is open-ended (e.g. "top up-and-coming tech companies"), first find concrete candidates: use finance_data (action=search) to resolve names to tickers, and web search / the browser for qualitative discovery.
2. For EVERY ticker you discuss, pull real data with the finance tools:

• finance_data action=analyze — LIVE price, % returns, 52-week range position, and the indicator panel (RSI-14, MACD, SMA 50/200, VWMA-20/67, trend). Batch multiple tickers in one call.
• finance_data action=fundamentals — market cap, P/E & forward P/E, PEG, margins, revenue growth, analyst target & rating (use for valuation).
• finance_data action=quote source=pyth — fastest realtime spot price (esp. crypto) with a confidence band, when you need the very latest tick.
• finance_data action=liquidation — the VWMA-67 'true price' and leverage liquidation levels (great for crypto/timing context).
• finance_news — recent catalysts/sentiment (macro + per-ticker headlines).
• finance_insider — corporate insider (SEC Form 4) and, with scope=congress, political trades, to see informed-money flow. If scope=congress returns a browser_fallback (the free API was gated), follow it: use the browser tool on the given capitoltrades.com URL(s) and read the rendered trades table.

3. Writing a concise report: a short investment thesis for each asset (why it is interesting, grounded in the pulled price/fundamentals/news/insider data), then a summary table with columns: Ticker | Price | 1d% | 5d% | 20d% | RSI | P/E | Trend. Rank assets by thesis strength, cite notable news/insider signals, and clearly flag any ticker you could not fetch.

REQUEST: How did the US stock market perform today, including the major indices, the biggest movers, and what drove them?

Date: 2026-09-18T04:52:53.820104647+00:00

Coverage window: 2026-09-18 – 2026-09-18

Rounds: 1

Status: PARTIAL

Objective check — 0 of 6 criteria met

The run produced work, but the objective below is not fully achieved. Each unmet criterion names what is still outstanding.

• UNVERIFIABLE — The report states a closing (or last-available same-day) level and percent change for the S&P 500, Nasdaq Composite, Dow Jones Industrial Average, Russell 2000 and VIX, each traceable to a finance-tool pull or a 2026-09-18-dated source URL
  • the grader returned no verdict for this criterion
• UNVERIFIABLE — The report names at least 5 specific tickers that were among the session's biggest gainers or losers on 2026-09-18, with each one's same-day percent move and a cited causal driver
  • the grader returned no verdict for this criterion
• UNVERIFIABLE — The report identifies the macro catalyst(s) actually in play on 2026-09-18 (e.g. FOMC decision/minutes, a named economic data release, quarterly options expiration) with the announcement date confirmed as 2026-09-18
  • the grader returned no verdict for this criterion
• UNVERIFIABLE — The report gives a same-day performance read for the 11 GICS sectors or, at minimum, names which sectors led and lagged on 2026-09-18
  • the grader returned no verdict for this criterion
• UNVERIFIABLE — The report includes cross-asset context for 2026-09-18 (at least the US 10-year Treasury yield plus two of: DXY, WTI crude, gold, Bitcoin) with sourced values
  • the grader returned no verdict for this criterion
• UNVERIFIABLE — Any ticker or index the swarm could not fetch is listed in an explicit 'unfetched' section with the reason
  • the grader returned no verdict for this criterion

Evidence: 115 claims · 46 sourced · 5 partial · 6 unsupported · 55 self-reported (no independent source) · 17 single-source

Executive Summary

As of 2026-09-18, the US market has not traded. There is no 2026-09-18 close for any major index, no same-day gainers/losers list, and no session driver to attribute — because at the time this was pulled, the regular session had not opened. The New York clock read 12:44 AM ET on Friday, September 18, 2026, status "closed," with "Time until open: 8:45:19" (investomatica.com/is-stock-market-open); a second live status page returned the same verdict at 12:31 AM ET (regardsofwallstreet.com/tools/market-hours). Every index series in the finance tool terminates at the 2026-09-17 session — the SPX, IXIC, DJI, VIX daily bars all carry last_bar: 2026-09-17, and the 5-minute feed ends 2026-09-17 20:00 UTC (16:00 ET, the closing bell).

The market is scheduled to open today (Friday, September 18, 2026 is a normal trading day). What follows is therefore the last completed session, kept strictly labelled as such, plus the verified pre-open setup for today.

Last completed session — Thursday 2026-09-17 (not today):

The Dow figure appears as 51,783.17 on the TVC:DJI series and 51,778.04 on the ^DJI quote in the same run; the VIX print is low confidence because its daily bar timestamp is anomalous (2026-09-17 07:15 UTC, pre-cash-session) even though the VIX 5-minute feed runs to 20:10 UTC. AP's wrap — the newest index wrap in existence, titled "How major US stock indexes fared Thursday 9/17/2026" (apnews.com) — independently reports the S&P 500 at 7,637.76, +1.1%, Dow +0.6%, Nasdaq +1.7%, matching the pulls to the cent.

Summary table (all rows = 2026-09-17, the last completed session; P/E not fetched):

Biggest movers on 2026-09-18: none found. No same-day mover screen exists to pull (the session had not traded), and finance_news returned zero headlines on two attempts (FinancialJuice HTTP 429), so no ticker-level price move with a cited 2026-09-18 driver was sourced. Naming five movers here would be fabrication.

What Is Actually Confirmed for 2026-09-18 (in-window)

The only genuinely 2026-09-18-dated market print obtained anywhere was Bitcoin $77,205.94, +1.123% (Coinbase bar stamped 2026-09-18 00:00), because crypto trades through the US overnight.

Analysis

What drove the 2026-09-17 session (background, outside your window): a post-Fed-hike retracement, not a same-day Fed reaction. The FOMC acted on 2026-09-16, raising the target range 25bp to 3.75%–4.00% — reported as the first Fed hike since 2023, under Chair Warsh, with reserve-balance rate moved to 3.90% effective Sept 17 (federalreserve.gov implementation note; corroborated by CNBC, KPMG, Fox Business). Sept 17's rebound came as bond yields eased and oil retreated — the 10-year fell below 5% (tool pulls: 4.941%–4.947%; AP: 4.93% — the three disagree slightly) and Brent slipped ~1%. Nasdaq +1.69% versus Dow +0.61%, with the Dow's 50-day SMA above price and a negative 20-day return, is a narrow, tech-led bounce inside a still-weak broader/small-cap structure. One snippet-level source (tickerdaily.com) claims "Fed rate cut bets" for the same session, flatly contradicting the hike framing — a contradiction this report does not resolve.

Sector colour for 2026-09-17 (cap-weighted): nine of eleven GICS sectors closed higher; Technology led at +2.25% (XLK $188.06, validated to the cent against the tool pull) and Communication Services lagged at −0.58% (XLC $112.35), with Financials the only other decliner (−0.09%). On a median-stock basis, Materials led (+1.69%) and Technology was third (+0.97%) — both can be true: tech's gain was megacap-carried. Breadth was 73% of liquid names up (4,216 of 5,811) (thedesperatetrader.com, stockbase.com). Sector ranking for 2026-09-18: no dated in-window source found.

A trap worth naming: at least five pages carry a "September 18, 2026" header while serving September 17 numbers. stockbase.com ("Data as of Sep 18, 2026 (prior close)") and whyisstock.com both reproduce the Sept-17 prints exactly; convextrade.com labels SPY's Sept-17 close as the "S&P 500." Any recap reading the header date and reporting the numbers beneath it is reporting yesterday.

Risks & Open Questions

• The core answer is a timing answer. Re-run after 16:00 ET today; the moment the daily bar reads 2026-09-18, the requested close/mover/driver table becomes producible. AP will publish "How major US stock indexes fared Friday 9/18/2026" as an independent cross-check.
• Symbol layer is broken and inconsistent across pulls. Caret forms ^GSPC, ^IXIC, ^DJI, ^RUT, ^VIX returned "no data on any exchange" across 18 exchanges tried; bare RUT and IWM failed in one run and succeeded in another. There is no directly-fetched Nasdaq Composite alternative to IXIC and no working VIX symbol other than the TVC series with the anomalous timestamp.
• finance_data quote source=pyth failed wholesale (HTTP Error 401: Unauthorized) for SPY, QQQ, DIA, IWM, VIX, SPX, NDX, BTCUSD, so no realtime spot tick with a confidence band was obtainable.
• No P/E, forward P/E, PEG, or margin data exists for any ticker here — finance_data action=fundamentals was never successfully run. finance_insider (Form 4 and congressional scope) was also never run, so no informed-money flow for 2026-09-18 can be reported; that is an evidence gap, not a null signal.
• Quad witching on 2026-09-18 is conditionally true. The third-Friday rule makes it so, and multiple calendars agree, but no exchange or OCC primary record was reached. If it holds, expect elevated volume and pinning into the close — a structural feature of today's tape, not a driver of it.

Claims without independent support

These statements appear in the narrative above but are not backed by text retrieved from a source. SELF-REPORTED means the only thing asserting it is the swarm's own worker output — the narrative was written from that output, so it corroborates nothing. Treat all of these as unverified.

• [SELF-REPORTED] What follows is therefore the last completed session, kept strictly labelled as such, plus the verified pre-open setup for today.
• [UNSUPPORTED] 1d %
• [UNSUPPORTED] 5d %
• [SELF-REPORTED] +1.138%
• [SELF-REPORTED] +0.607%
• [SELF-REPORTED] −0.911%
• [SELF-REPORTED] 88.1%
• [SELF-REPORTED] 26,418.30
• [SELF-REPORTED] +1.693%
• [SELF-REPORTED] +1.290%
• [SELF-REPORTED] +0.331%
• [SELF-REPORTED] 29,446.98
• [SELF-REPORTED] +1.734%
• [SELF-REPORTED] +0.071%
• [SELF-REPORTED] 83.4%
• [SELF-REPORTED] 51,783.17
• [SELF-REPORTED] +0.614%
• [SELF-REPORTED] −0.549%
• [SELF-REPORTED] −3.152%
• [SELF-REPORTED] 69.4%
• [SELF-REPORTED] 2,874.63
• [SELF-REPORTED] +0.553%
• [SELF-REPORTED] 74.5%
• [SELF-REPORTED] 15.44
• [SELF-REPORTED] −12.818%
• [SELF-REPORTED] −13.453%
• [SELF-REPORTED] +3.694%
• [SELF-REPORTED] 9.4%
• [SELF-REPORTED] Summary table (all rows = 2026-09-17, the last completed session; P/E not fetched):**
• [UNSUPPORTED] 1d%
• [UNSUPPORTED] 5d%
• [SELF-REPORTED] −0.91%
• [SELF-REPORTED] 49.6
• [SELF-REPORTED] +1.29%
• [UNSUPPORTED] 53.9
• [SELF-REPORTED] +1.73%
• [SELF-REPORTED] 52.9
• [SELF-REPORTED] −0.84%
• [SELF-REPORTED] 716.92
• [SELF-REPORTED] +1.16%
• [UNSUPPORTED] 39.3
• [SELF-REPORTED] 518.35
• [SELF-REPORTED] −0.46%
• [SELF-REPORTED] −2.98%
• [SELF-REPORTED] 39.7
• [SELF-REPORTED] 36.9
• [SELF-REPORTED] 285.43
• [SELF-REPORTED] +0.53%
• [SELF-REPORTED] −0.79%
• [SELF-REPORTED] −5.40%
• [SELF-REPORTED] 36.1
• [SELF-REPORTED] −12.82%
• [SELF-REPORTED] −13.45%
• [SELF-REPORTED] +3.69%
• [SELF-REPORTED] 47.6
• [SELF-REPORTED] Biggest movers on 2026-09-18: none found.** No same-day mover screen exists to pull (the session had not traded), and finance_news returned zero headlines on two attempts (FinancialJuice HTTP 429), so no ticker-level price move with a cited 2026-09-18 driver was sourced. Naming five movers here would be fabrication.
• [PARTIAL] +25bp to 1.25%, highest since 1995; vote split 7–2 (Asada, Sato dissent); Japan Aug CPI 1.9% (core 1.7%) (unmatched: 1.25, 1995, 1.9)
• [PARTIAL] Confirmed, wire-timestamped 2026-09-18T02:56–04:05Z (financialjuice.com) (unmatched: 9768655)
• [PARTIAL] USD/JPY +0.68% to 157, highest since Sept 3; AUD/JPY +1.04%, EUR/JPY +0.82% (unmatched: 0.68, 157, 0.82)
• [PARTIAL] The only genuinely 2026-09-18-dated market print obtained anywhere was Bitcoin $77,205.94, +1.123% (Coinbase bar stamped 2026-09-18 00:00), because crypto trades through the US overnight. (unmatched: 77205.94, 1.123)
• [SELF-REPORTED] What drove the 2026-09-17 session (background, outside your window):** a post-Fed-hike retracement, not a same-day Fed reaction.
• [PARTIAL] Sept 17's rebound came as bond yields eased and oil retreated — the 10-year fell below 5% (tool pulls: 4.941%–4.947%; AP: 4.93% — the three disagree slightly) and Brent slipped ~1%. (unmatched: 4.941)
• [SELF-REPORTED] Symbol layer is broken and inconsistent across pulls. Caret forms ^GSPC, ^IXIC, ^DJI, ^RUT, ^VIX returned "no data on any exchange" across 18 exchanges tried; bare RUT and IWM failed in one run and succeeded in another.
• [SELF-REPORTED] There is no directly-fetched Nasdaq Composite alternative to IXIC and no working VIX symbol other than the TVC series with the anomalous timestamp.
• [SELF-REPORTED] finance_data quote source=pyth failed wholesale (HTTP Error 401: Unauthorized) for SPY, QQQ, DIA, IWM, VIX, SPX, NDX, BTCUSD, so no realtime spot tick with a confidence band was obtainable.
• [SELF-REPORTED] No P/E, forward P/E, PEG, or margin data exists for any ticker here — finance_data action=fundamentals was never successfully run.

Detailed Findings

Round 0 · Finding 1

US Market Recap — 2026-09-18: No Completed Session Data Exists Yet; No Same-Day Single-Stock Catalysts Verifiable

1. Executive Summary — the honest headline

The premise of the request cannot be satisfied from live data as of this research pass. Every market feed I pulled ends at the 2026-09-17 session, and every 2026-09-18-dated page I reached is a pre-open artifact. The 2026-09-18 US regular session had not yet opened (or had not yet been captured by any feed) at the time of pulling. Specifically:

• finance_data (analyze, daily and 5-minute) returned last_bar: 2026-09-17 for every US instrument. The 5-minute feed's final bar is 2026-09-17 19:55 (post-close), i.e. nothing from 2026-09-18 exists in the feed.
• CNBC's live blog for the session is timestamped "Updated Fri, Sep 18 2026 12:03 AM EDT" — 12:03 AM ET, roughly 13 hours before the 9:30 AM ET open — and its content is futures and Asian markets, not a US close. (https://www.cnbc.com/2026/09/17/stock-market-today-live-updates.html)
• A page explicitly headlined for the 9/18 close ("US Stock Market Today Sep 18, 2026") is JavaScript-rendered and returned no numbers on fetch; its own generator timestamp reads 18 Sep 2026 · 10:00 IST (00:30 ET). (https://vittarthi.com/markets/us)

Therefore: I am reporting NO index closes, NO percent moves, and NO biggest-movers list for 2026-09-18, because no such same-day prints are available to me. Fabricating them is prohibited by the mission's anti-goals. What follows is the verified setup for 2026-09-18 plus the labeled prior-session (2026-09-17) baseline, kept strictly separated.

Direct answer to the specific sub-question (company-specific catalysts on 2026-09-18): I found zero verified in-window single-stock catalysts. No earnings, guidance, M&A, analyst-action, regulatory/litigation, or index-inclusion event dated 2026-09-18 with a same-day price move could be sourced. Details and the specific gaps are listed in §5 and §6.

2. Key Findings (with confidence levels)

…(truncated — the summary above captures the substance)

Round 0 · Finding 2

US Stock Market — Session Recap Requested for 2026-09-18

1. Executive Summary

The 2026-09-18 US regular trading session had not yet occurred at the time of this research, so no closing levels, percent changes, movers, sector prints, or session catalysts exist for it. This is not a data-gathering failure on the index feed alone — it is confirmed by an independently fetched market-status page.

At the moment of research, the New York clock read 12:44:40 AM ET on Friday, September 18, 2026, with "Time until open: 8:45:19" and "Current Status: closed" (investomatica.com/is-stock-market-open, page fetched 2026-09-18). The US open (9:30 ET) was still ~8h45m away.

Correspondingly, every US index series in the finance tool terminates at the 2026-09-17 session — the last completed session:

• S&P 500 (SPX) daily last bar: 2026-09-17 13:30:00 (UTC)
• Nasdaq Composite (IXIC) daily last bar: 2026-09-17 13:30:00
• Dow (DJI) daily last bar: 2026-09-17 13:30:00
• VIX daily last bar: 2026-09-17 07:15:00
• SPX 5-minute last bar: 2026-09-17 20:00:00 (16:00 ET, the closing bell)
• VIX 5-minute last bar: 2026-09-17 20:10:00 (16:10 ET)

Because the mission's anti-goals explicitly forbid presenting pre-2026-09-18 data as "today's" performance, I am not labeling the 2026-09-17 prints as the 2026-09-18 session. I report them below as the last completed session, clearly labeled, with the 2026-09-18 close marked as not yet available.

Bottom line: the requested headline answer — how the US market performed today, 2026-09-18 — cannot be answered yet, because the session has not traded.

2. Key Findings

Finding 1 — No 2026-09-18 US session data exists yet (Confidence: HIGH)

Verified from two independent angles: (a) the finance tool's most recent bar for every US index is 2026-09-17; (b) an independently fetched status page states the market is closed at 12:44 AM ET on 2026-09-18 with the open 8h45m away (investomatica.com, fetched 2026-09-18).

A third, corroborating signal: the auto-generated market-summary site Vittarthi publishes a page titled "US Stock Market Today Sep 18, 2026 — S&P 500, Dow & Nasdaq Close," but its 18 Sep tab is an empty template — section headers ("● Key Indices / How the headline indices closed," "● Top Movers," "● Sectors") render with no values, and the only generated timestamp for 18 Sep is "10:00 IST" (00:30 ET), pre-open. Its 17 Sep tab is the last one populated (vittarthi.com/markets/us, fetched 2026-09-18).

Finding 2 — Last completed session: 2026-09-17 (Confidence: HIGH for the numbers; they are tool pulls, not memory)

All figures below are finance_data action=analyze outputs. These are 2026-09-17 prints, not 2026-09-18 prints.

…(truncated — the summary above captures the substance)

Round 0 · Finding 3

Cross-Asset & Rates Backdrop Framing the US Equity Session — 2026-09-18

⚠️ Read this first: the same-day cross-asset read could not be obtained

This is the central finding, and it is a data-availability finding, not a market call.

Every market-data feed I could reach terminates at the 2026-09-17 US close. I pulled finance_data in four separate calls (quote, analyze, history 1d, history 1h) across indices, ETFs, futures and crypto. The newest bar returned by any of them is 2026-09-17 19:30 UTC. There is no 2026-09-18 bar anywhere in the tool, and finance_data action=quote source=pyth returned HTTP 401 Unauthorized for both BTCUSD and ETHUSD, so no realtime crypto spot with confidence band was obtainable either. finance_news returned 0 results (its financialjuice source returned HTTP 429 Too Many Requests).

I therefore cannot report a 2026-09-18 level or same-day percent move for the 10-year yield, the 2-year yield, the dollar index, WTI, gold or Bitcoin. Reporting the 2026-09-17 values below as "today's" would violate the explicit constraint against presenting pre-2026-09-18 data as same-day performance. They are labelled as the last-available session, which is a different thing.

1. Cross-asset & rates table — LAST AVAILABLE SESSION (2026-09-17), explicitly NOT 2026-09-18

All values below are tool-computed, pulled live from finance_data (action=analyze / quote / history). last_bar: 2026-09-17 13:30:00 on every series.

…(truncated — the summary above captures the substance)

Round 0 · Finding 4

US Market Recap — Session of Friday 2026-09-18

Headline finding: the 2026-09-18 US session had not opened when this research was run

The requested deliverable — a recap of the 2026-09-18 US trading session — cannot be produced, because that session had not yet begun. This is not a data-availability failure on my side; it is the state of the world at the time of research.

A live market-status page fetched during this run states explicitly, for New York on Friday, September 18:

"Closed No trading · Friday, September 18 · New York — Not yet. It is before the pre-market open; the regular session starts at 9:30am ET." — https://www.regardsofwallstreet.com/tools/market-hours

The same page's overnight-futures readout is timestamped 12:31am ET: "S&P 500 futures are up 0.11% in overnight trading at 12:31am ET after the S&P 500 closed up 1.1% on Thursday, the first read on Friday's open." (same URL)

Corroboration from the finance tool (independent of any web page): every finance_data action=analyze call I made returned a last completed daily bar of 2026-09-17 13:30:00 — across all 11 sector ETFs, SPY/QQQ/DIA/IWM/TLT/GLD, SPX, NDX, VIX, US10Y and DXY. The only instrument with a genuinely 2026-09-18-dated bar was Bitcoin (24/7 market), at 2026-09-18 00:00:00.

Four converging signals therefore place "now" at roughly midnight–1:00am ET on Friday 2026-09-18: (1) the live status page above; (2) every finance-tool series ending 2026-09-17; (3) a Sep-18-dated outlook page whose own footer reads "Updated September 17, 2026 at 04:30 PM ET" (https://strongbuyanalytics.com/stock-market-outlook); (4) a Sep-18-dated aggregator whose Sep-18 entry is generated at "10:00 IST" = 00:30 ET, i.e. pre-open (https://vittarthi.com/markets/us).

There are no 2026-09-18 regular-hours index closes, sector moves, or single-stock moves in existence to report. Per the mission's explicit constraint, I will not back-fill 2026-09-17 prints as "today's" performance.

The trap: five pages dated "September 18, 2026" that are actually carrying September 17 data

This is the single most important methodological finding of this run, and it is why the mission's anti-goals matter. Every "Sep 18" sector/market page I fetched was serving the September 17 close under a September 18 date header. Two of them I could prove it against my own tool pulls:

…(truncated — the summary above captures the substance)

Round 0 · Finding 5

US Market Session Recap — 2026-09-18

1. Executive Summary — the headline finding is a calendar correction

As of the timestamp of this research (Fri Sep 18, 2026, 00:45:47 ET, verified live via browser clock: {"now":"Fri Sep 18 2026 00:45:47 GMT-0400 (Eastern Daylight Time)","iso":"2026-09-18T04:45:47.463Z"}), the US regular trading session for 2026-09-18 has not opened. There is therefore no S&P 500 / Nasdaq / Dow / Russell 2000 / VIX close and no percent change for the 2026-09-18 session to report. Any source claiming a 2026-09-18 close is reporting something that has not happened.

Accordingly, this report does two things, and keeps them strictly separate:

• Part A — the tape that actually exists: the last completed US session, Thursday 2026-09-17, with every level and percent change pulled live from the finance tools in this run.
• Part B — the actual question asked (the 2026-09-18 event calendar): verified findings on whether an FOMC event, a named US data release, or quarterly options/futures expiration fell on 2026-09-18.

Bottom line on the macro calendar: the Fed's rate decision was 2026-09-16, not 2026-09-18 — attributing today's (not-yet-existing) tape to a same-day FOMC action would be exactly the failure mode this task warned about. The one event genuinely scheduled for 2026-09-18 is quarterly options/futures expiration ("triple/quadruple witching"), plus an already-released Bank of Japan 25bp rate hike in the Asian morning.

2. Part A — The last completed session: Thursday 2026-09-17

All values below are live pulls from finance_data in this run, on the 2026-09-17 daily bar (last_bar: "2026-09-17 13:30:00" for the index series; Yahoo quote previous_close cross-checks confirm the same session). These are prior-session prints, explicitly NOT today's performance.

…(truncated — the summary above captures the substance)

Round 0 · Finding 6

US Market Session Recap — 2026-09-18: NOT AVAILABLE

1. Executive Summary

I could not produce the requested 2026-09-18 session recap, because no 2026-09-18 US trading-session prints exist in any source I could reach. The most recent completed US session in every data channel I pulled is Thursday 2026-09-17. As of my research time (approximately 04:05 UTC / 00:05 ET on 2026-09-18, per the newest news timestamp I could retrieve), the US cash session for Friday 2026-09-18 had not yet opened — the NYSE/Nasdaq open is 13:30 UTC.

I am therefore not reporting index closes, movers, or sector performance "for today," because doing so would require inventing them. Everything below is either (a) the explicit evidence that the 09-18 session is unavailable, or (b) the last-available session (2026-09-17), labelled as out-of-window background and not presented as today's performance.

Confidence in the core finding (no 09-18 US session data exists yet): HIGH.

2. Evidence that the 2026-09-18 session had not printed

…(truncated — the summary above captures the substance)

Investigation Trail

Round 0

• What were the closing levels and daily percent changes for the S&P 500 (^GSPC), Nasdaq Composite (^IXIC), Dow Jones Industrial Average (^DJI), Russell 2000 (^RUT) and CBOE Volatility Index (^VIX) for the US trading session on 2026-09-18? Pull live data with finance_data action=analyze (batch all tickers in one call) and report each index's last price, 1d%, 5d%, 20d%, 52-week range position, RSI-14, SMA 50/200 trend, and whether it closed up or down on the day.
• Which specific publicly-traded stocks were the biggest movers in the US market on 2026-09-18 — the largest S&P 500 / Nasdaq gainers and losers by daily percent change? Identify at least 5-10 named tickers with their ticker symbol, company name, same-day percent move and price, and then confirm each with finance_data action=analyze (batched). Use finance_news for 2026-09-18 headlines on each of those tickers.
• What macro news and scheduled events moved the US market on 2026-09-18? Specifically check whether there was a Federal Reserve FOMC decision, statement, press conference or minutes release dated 2026-09-18, whether any named US economic data (e.g. CPI, PCE, nonfarm payrolls, jobless claims, retail sales, PMI) was released that morning, and whether 2026-09-18 was a quarterly options/futures expiration ('quadruple witching') session. Use finance_news for same-day macro headlines and web search for the official BLS/Fed/BEA release pages dated 2026-09-18.
• How did the 11 GICS sectors perform on 2026-09-18 — which sectors led and which lagged, and what were the approximate same-day percent moves? Use finance_data action=analyze on the sector ETF proxies (XLK, XLF, XLE, XLV, XLI, XLY, XLP, XLU, XLRE, XLB, XLC) batched in one call, plus finance_news for 2026-09-18 sector rotation commentary. Report each ETF's 1d% and trend.
• Which individual company-specific catalysts drove notable single-stock moves on 2026-09-18 — earnings reports, guidance changes, M&A announcements, analyst upgrades/downgrades, regulatory or litigation news, or index-inclusion/exclusion changes? List each company/ticker, the specific catalyst, the catalyst's date (must be 2026-09-18) and the resulting same-day stock move. Cross-check with finance_news for 2026-09-18 and, where relevant, finance_insider for any SEC Form 4 insider filings dated 2026-09-18.
• What was the cross-asset and rates backdrop on 2026-09-18 that framed the US equity session? Pull same-day values for the US 10-year Treasury yield (^TNX), US 2-year yield, the US Dollar Index (DX-Y.NYB or UUP), WTI crude (CL=F or USO), gold (GC=F or GLD) and Bitcoin (BTC-USD, using finance_data action=quote source=pyth for the latest spot with confidence band). Report each level and same-day percent move, and note whether the moves were risk-on or risk-off consistent with the equity tape.

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Trace Index

Tool-call traces are persisted under /srv/swarm_web_runs/run-1789706401077-0013/finance_output/traces.