LLM trading agents — the evidence
1. The executive answer
No credible evidence exists that an LLM trading agent produces risk-adjusted alpha net of costs. The literature splits cleanly:
| Claim | Status |
|---|---|
| LLMs extract sentiment from news better than lexicon methods | ✅ well supported |
| LLM sentiment scores correlate with subsequent returns in-sample | ✅ supported, but heavily contaminated by lookahead |
| That correlation survives realistic transaction costs | ❌ fails at ~20 bps round-trip — by Lopez-Lira & Tang's own numbers |
| Multi-agent debate beats one well-prompted agent | ❌ not established; the general MAD literature finds the opposite |
| Reported Sharpe ratios of 5–8 are real | ❌ artifacts of 3-month windows, 3 tickers, zero costs, a bull regime |
| LLM agents beat buy-and-hold in a contamination-free setting | ❌ margin inside noise; in the one real-money competition, 4 of 6 models lost money |
The one well-designed study kills its own strategy. Lopez-Lira & Tang (arXiv 2304.07619) is genuinely post-cutoff and reports a gross Sharpe of 2.97. Its cost curve: ~700% at 0 bps → >300% at 5 bps → >100% at 10 bps → unprofitable at 20 bps round-trip. That curve, not a point estimate, is the format this field should have adopted.
Alpha Arena S1 (Oct 18 – Nov 3 2025, real capital): 4 of 6 models lost money; GPT-5 finished −59%; fees alone ate $1,654 of Qwen3's $10k. 🚨 The widely circulated "+79%" is a mid-competition snapshot, not a result — the same model finished at +22%.
StockBench contradicts itself: its abstract says "most models struggle to outperform" while its results section says "most tested models outperform." The real edge is ~2pp over 4 months gross, Sortino ~0.03, index-level drawdowns — inside noise.
2. 🚨 Contamination is the first thing to check, not the last
An LLM has memorized the period you are backtesting. Before any result is meaningful:
- State the backbone model's training cutoff against the backtest window. If they overlap, the result is uninterpretable until you show otherwise.
- Run a date probe. Ask the model directly about outcomes inside the test window; measure how its accuracy changes at the cutoff boundary. A discontinuity at the cutoff is the signature.
- Note that the one paper arguing lookahead is not a big deal (Glasserman & Lin) makes that claim only for headline sentiment — it is contradicted for general forecasting by Sarkar & Vafa, Levy (JAR 2026), and the cutoff-collapse result in Gao et al.
scripts/contamination_probe.py implements the date probe. Nothing else in the skills ecosystem
does this — it is the cheapest check that invalidates the largest class of published results.
3. The evidentiary bar
Any strategy result reported through this library must supply all of:
- Model training cutoff vs backtest window, with a contamination check.
- A cost-sensitivity curve — returns at 0 / 5 / 10 / 20 / 50 bps round-trip, not a point estimate. (Lopez-Lira & Tang's is the format the field should have adopted; almost nobody has.)
- Factor-adjusted alpha — CAPM minimum, preferably FF5 + momentum, with t-stats.
- Trial count and Deflated Sharpe Ratio — see
backtest-validation. - Regime coverage — at least one drawdown regime. A single bull quarter is not a backtest.
- An equal-budget single-agent baseline, if the design is multi-agent. No finance multi-agent paper has run this ablation.
- Turnover and capacity.
4. Frameworks — what they are, and what to believe
TradingAgents (arXiv 2412.20138) has the most legible architecture — fundamental/sentiment/news/
technical analysts, bull-bear debate, trader, risk team, portfolio manager. ✅ From its own tables:
the Sharpe 8.21 headline is 3 tickers over 60 trading days (2024-01-01 to 2024-03-29), backbones
o1-preview/gpt-4o, and transaction costs are never mentioned anywhere in the paper. Its
102,425 stars measure virality, not validity. Use it as a design reference and a challenger, never
as evidence.
🚨 Multi-agent debate is unsupported in general, not just in finance. arXiv 2502.08788 (retitled "Stop Overvaluing Multi-Agent Debate") finds MAD fails to beat single-agent chain-of-thought across 5 methods × 9 benchmarks × 4 models; arXiv 2510.20963 shows competitive MAD degenerates into cheap talk — exactly the bull/bear structure these frameworks use. No finance paper has run the equal-budget ablation.
🚨 Framework licence landmines: TradingAgents-CN has a proprietary core. AlphaAgent, StockAgent, FinCon and both openbb-agents repos have NO licence = all rights reserved. OpenBB is AGPL-3.0 (the GitHub API reports NOASSERTION — trust the LICENSE file).
⚠️ Vaporware check: FinCon (NeurIPS 2024) has no code — an 18 KB repo with one README and a "3–4 month" release promise now 6+ months expired. FinAgent has no official repo. FinNLP and FinMem have been dead ~2 years.
Microsoft RD-Agent (14,480★, MIT, very active) is the most defensible of these: an offline hypothesis→implement→feedback loop for factor and model research. 🚨 Every candidate it generates is a trial and must enter the ledger — an automated search inflates the multiple-testing problem faster than any human can.
FinGPT / FinRL / FinNLP / FinRobot (AI4Finance): FinGPT is a language component, not a trading system; FinRobot's perception/brain/action layering is useful for report generation, but wiring its action layer to execution carries semantic uncertainty across the order boundary.
🚨 FinRL does not install. ✅ Verified: its 0.3.7 wheel (2024-04-12) declares
requires_dist: None, so pip install finrl pulls zero dependencies and import finrl dies
on ModuleNotFoundError. elegantrl and finrl-meta share the failure mode and have been frozen
since 2023-02-07. See ../rl-and-ml-trading/SKILL.md for the verified state of the whole RL
stack and the evidence on whether any of it works.
Do not install these into a production environment to "evaluate" them. Each brings its own data sources, caches, prompts, state and execution assumptions, which destroys the auditability of whatever you already have. Read the architecture; port the one idea you want.
5. FinBERT and the licence problem
🚨 The most-downloaded financial NLP models declare no licence at all. Verified via the HuggingFace API (downloads = last 30 days):
| Model | Downloads/30d | Licence |
|---|---|---|
ProsusAI/finbert |
4,926,116 | 🔴 NONE |
yiyanghkust/finbert-tone |
792,989 | 🔴 NONE |
mrm8488/distilroberta-finetuned-financial-news-sentiment-analysis |
321,764 | apache-2.0 |
yiyanghkust/finbert-esg / finbert-pretrain |
58k / 56k | 🔴 NONE |
StephanAkkerman/FinTwitBERT-sentiment |
70,593 | 🟢 MIT |
No licence = all rights reserved. The single most-used financial sentiment model in the world has no grant of rights. If the work is commercial, this matters; prefer the MIT/Apache options.
6. Where this library sits
✅ anthropics/skills (the official repo, 173,666★) contains ZERO finance, trading or investing
skills. There is no first-party anchor; the ecosystem is entirely community-built and quality
varies by two orders of magnitude.
Do not duplicate — cite and move on:
- Crypto/DeFi/Solana execution, MEV, prediction markets →
agiprolabs/claude-trading-skills(68 skills, MIT) - RIA compliance, KYC/AML, Reg BI, GIPS, practice ops →
JoelLewis/finance_skills(91 skills, MIT) - Personal/SMB bookkeeping and tax →
openaccountant/skills(44 skills, MIT) - Leakage-safe quant ML methodology →
ml4t/skills(Stefan Jansen, 60 skills, Apache-2.0) is already excellent. Build on it or differentiate deliberately; do not silently re-implement it worse. - ⚠️
quantskills/*is GPL-3.0 with vendor lock-in.ALAGENT-HKU/x2strategyhas no licence.
The gap this library fills: the ecosystem is saturated at both ends — API wrappers and knowledge
dumps — and nearly empty in the middle, at the methodology that decides whether a result is real.
That is what research-integrity-guards and backtest-validation are for.
7. Regulatory facts that changed recently
🚨 The Pattern Day Trader rule was ELIMINATED effective 2026-06-04 (SEC Release 34-105226), replaced by intraday margin. Keep PDT in the backtester for historical periods; delete it from live paths. Rule state must be keyed to date.
🚨 Reg SHO Rule 201: after a 10% intraday drop, short sales may only be filled above the national best bid. This breaks exactly the mean-reversion backtests that claim the most edge — shorting into a crash is often not executable at the price the backtest assumed.
✅ T+1 settlement since 2024-05-28. ✅ The SEC's predictive-data-analytics / AI proposal was withdrawn 2025-06-17 — do not build to it.
Also: the SEC Marketing Rule (206(4)-1, with March 2025 and January 2026 FAQs) governs presenting
hypothetical/backtested performance; personalized investment advice is regulated under the Investment
Advisers Act — an LLM must not give it; and market-data redistribution terms differ per vendor on
caching, redistribution, derived works and non-display use. See references/_regulatory.md.
⚠️ Financial NLP training data is legally contaminated too: Financial PhraseBank is
CC BY-NC-SA 3.0 and FiQA is non-commercial with no formal grant — so ProsusAI/finbert, itself
unlicensed, is fine-tuned on non-commercial data. SEC EDGAR is the only clean text source.
8. Reference files
references/<framework>.md — architecture, maintenance, licence, and an honest reading of its
published results. references/_evidence-papers.md — the citation list with arXiv IDs and what each
paper actually measured.