Backtest trading strategies with historical data. An agent skill from Signal-Execution-Labs/forex-trading-ai-agent.

MITAuto-check passedBusiness, Finance & HR

Install Backtester

skills CLI
$ npx skills add Signal-Execution-Labs/forex-trading-ai-agent --skill backtester -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install Signal-Execution-Labs/forex-trading-ai-agent backtester --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/Signal-Execution-Labs/forex-trading-ai-agent.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/backtester .claude/skills/backtester && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
backtester
GitHub stars
162
Token cost
~2.7k tokens
SKILL.md length
153 words
Files
2 (incl. scripts)
Skills in repo
11
Repo updated
First seen
Licence
MIT

At a glance

Backtest trading strategies with historical data. An agent skill from Signal-Execution-Labs/forex-trading-ai-agent.

  • Works in 7 steps: Define Hypothesis - What pattern are you… → Gather Data - At least 1 year of… → Code Strategy - Clear entry/exit rules → …
  • Tasks that involve Trading and backtesting
  • SKILL.md covers Overview, Commands and Workflow
  • Runs Python scripts from its folder; calls python3

What it does

Backtester is an agent skill from Signal-Execution-Labs/forex-trading-ai-agent. Backtest trading strategies with historical data. Calculate performance metrics and generate reports.

Its SKILL.md is about 2.7k tokens, which your agent loads only when the skill is triggered. The skill folder holds 2 other files, including scripts (for example `scripts/backtest_runner.py`).

It sits in Business, Finance & HR, covering Trading and backtesting and OKRs and executive reporting. The repository describes itself as: About AI quantitative trading platform for crypto, stocks, and forex with backtesting, live trading, market data, and multi-agent research.vibe-trading…. The licence is MIT.

When your agent uses it

  • Tasks that involve Trading and backtesting
  • Tasks that involve OKRs and executive reporting

Example prompts

  • “/backtester”

Requirements

  • Python 3

Workflow steps

7 steps, taken from the first numbered list in SKILL.md.

  1. Define Hypothesis - What pattern are you testing?
  2. Gather Data - At least 1 year of historical data
  3. Code Strategy - Clear entry/exit rules
  4. Run Backtest - Generate performance metrics
  5. Analyze Results - Look for overfitting
  6. Walk-Forward Test - Test on unseen data
  7. Paper Trade - Real-time validation

What it can do on your machine

Read from SKILL.md and the folder at commit b8a6047. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    Ships 1 file in scripts/ (Python), which the agent can run.

    Shell commands in SKILL.md call:

    • python3

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    No URLs in SKILL.md.

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Backtester loads about 2.7k tokens when it runs. Until then it costs about 28 tokens; SKILL.md has 153 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~28
When it runs · the whole SKILL.md, loaded when a task matches
~2.7k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.

SKILL.md

The full file from Signal-Execution-Labs/forex-trading-ai-agent at commit b8a6047, republished under its MIT licence (© Signal-Execution-Labs). 153 words, ~2,659 tokens.

Download SKILL.mdSave it as .claude/skills/backtester/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.
name
backtester
description
Backtest trading strategies with historical data. Calculate performance metrics and generate reports.

Backtester

Test trading strategies against historical data before risking real money.

Overview

  • Historical Data - Load OHLCV from exchanges
  • Strategy Testing - Simulate trades with rules
  • Performance Metrics - Win rate, Sharpe, drawdown
  • Report Generation - Detailed analysis

Commands

Load Historical Data
bash
python3 -c "
import ccxt
import pandas as pd
from datetime import datetime, timedelta

symbol = 'BTC/USDT'
timeframe = '1d'
exchange = ccxt.binance()

# Fetch 1 year of data
since = exchange.parse8601((datetime.now() - timedelta(days=365)).isoformat())
ohlcv = exchange.fetch_ohlcv(symbol, timeframe, since=since, limit=365)

df = pd.DataFrame(ohlcv, columns=['timestamp', 'open', 'high', 'low', 'close', 'volume'])
df['date'] = pd.to_datetime(df['timestamp'], unit='ms')

print(f'📊 HISTORICAL DATA: {symbol}')
print('=' * 50)
print(f'Timeframe: {timeframe}')
print(f'Period: {df[\"date\"].iloc[0].date()} to {df[\"date\"].iloc[-1].date()}')
print(f'Candles: {len(df)}')
print(f'Price Range: \${df[\"low\"].min():,.2f} - \${df[\"high\"].max():,.2f}')

# Save for backtesting
# df.to_csv(f'{symbol.replace(\"/\", \"_\")}_{timeframe}.csv', index=False)
"
Simple RSI Backtest
bash
python3 -c "
import ccxt
import ta
import pandas as pd
import numpy as np

# Load data
symbol = 'BTC/USDT'
exchange = ccxt.binance()
ohlcv = exchange.fetch_ohlcv(symbol, '1d', limit=365)
df = pd.DataFrame(ohlcv, columns=['timestamp', 'open', 'high', 'low', 'close', 'volume'])

# Calculate RSI
df['rsi'] = ta.momentum.RSIIndicator(df['close'], 14).rsi()

# Strategy: Buy RSI < 30, Sell RSI > 70
initial_capital = 10000
capital = initial_capital
position = 0
trades = []

for i in range(1, len(df)):
    rsi = df['rsi'].iloc[i]
    price = df['close'].iloc[i]
    
    if rsi < 30 and position == 0:  # Buy signal
        position = capital / price
        capital = 0
        trades.append({'type': 'buy', 'price': price, 'rsi': rsi})
    
    elif rsi > 70 and position > 0:  # Sell signal
        capital = position * price
        position = 0
        trades.append({'type': 'sell', 'price': price, 'rsi': rsi})

# Close final position
if position > 0:
    capital = position * df['close'].iloc[-1]

final_value = capital
total_return = ((final_value - initial_capital) / initial_capital) * 100
buy_hold_return = ((df['close'].iloc[-1] - df['close'].iloc[0]) / df['close'].iloc[0]) * 100

print(f'📊 RSI STRATEGY BACKTEST: {symbol}')
print('=' * 50)
print(f'Period: {len(df)} days')
print(f'Initial Capital: \${initial_capital:,.2f}')
print(f'Final Value: \${final_value:,.2f}')
print()
print(f'Strategy Return: {total_return:+.2f}%')
print(f'Buy & Hold Return: {buy_hold_return:+.2f}%')
print(f'Outperformance: {total_return - buy_hold_return:+.2f}%')
print()
print(f'Total Trades: {len(trades)}')
"
Moving Average Crossover Backtest
bash
python3 -c "
import ccxt
import ta
import pandas as pd
import numpy as np

symbol = 'BTC/USDT'
exchange = ccxt.binance()
ohlcv = exchange.fetch_ohlcv(symbol, '4h', limit=500)
df = pd.DataFrame(ohlcv, columns=['timestamp', 'open', 'high', 'low', 'close', 'volume'])

# Calculate EMAs
df['ema_12'] = ta.trend.ema_indicator(df['close'], 12)
df['ema_26'] = ta.trend.ema_indicator(df['close'], 26)

# Generate signals
df['signal'] = 0
df.loc[df['ema_12'] > df['ema_26'], 'signal'] = 1  # Long
df.loc[df['ema_12'] < df['ema_26'], 'signal'] = -1  # Out/Short

# Calculate returns
df['returns'] = df['close'].pct_change()
df['strategy_returns'] = df['signal'].shift(1) * df['returns']

# Performance metrics
total_return = (1 + df['strategy_returns'].fillna(0)).prod() - 1
buy_hold_return = (df['close'].iloc[-1] / df['close'].iloc[0]) - 1

# Calculate metrics
returns = df['strategy_returns'].dropna()
sharpe = np.sqrt(252 * 6) * returns.mean() / returns.std() if returns.std() > 0 else 0

# Drawdown
cumulative = (1 + returns).cumprod()
running_max = cumulative.cummax()
drawdown = (cumulative - running_max) / running_max
max_drawdown = drawdown.min()

print(f'📊 MA CROSSOVER BACKTEST: {symbol}')
print('=' * 50)
print(f'Period: {len(df)} candles (4h)')
print()
print('Performance:')
print(f'  Strategy Return: {total_return*100:+.2f}%')
print(f'  Buy & Hold: {buy_hold_return*100:+.2f}%')
print(f'  Sharpe Ratio: {sharpe:.2f}')
print(f'  Max Drawdown: {max_drawdown*100:.2f}%')
print()

# Win rate
trades = df[df['signal'] != df['signal'].shift(1)].copy()
print(f'Total Signals: {len(trades)}')
"
Full Backtest with Metrics
bash
python3 -c "
import ccxt
import ta
import pandas as pd
import numpy as np
from datetime import datetime

def backtest_strategy(df, strategy_func, initial_capital=10000):
    '''Generic backtester'''
    capital = initial_capital
    position = 0
    entry_price = 0
    trades = []
    equity_curve = [initial_capital]
    
    for i in range(50, len(df)):  # Start after indicator warmup
        signal = strategy_func(df, i)
        price = df['close'].iloc[i]
        
        if signal == 'buy' and position == 0:
            position = capital * 0.95 / price  # 5% reserved for fees
            entry_price = price
            capital = capital * 0.05
            trades.append({'type': 'buy', 'price': price, 'index': i})
        
        elif signal == 'sell' and position > 0:
            capital += position * price * 0.999  # 0.1% fee
            pnl = (price - entry_price) / entry_price * 100
            trades.append({'type': 'sell', 'price': price, 'pnl': pnl, 'index': i})
            position = 0
        
        equity = capital + position * price
        equity_curve.append(equity)
    
    return {
        'trades': trades,
        'equity_curve': equity_curve,
        'final_value': equity_curve[-1],
        'initial_capital': initial_capital
    }

def rsi_strategy(df, i):
    rsi = df['rsi'].iloc[i]
    if rsi < 30:
        return 'buy'
    elif rsi > 70:
        return 'sell'
    return 'hold'

# Load data and calculate indicators
symbol = 'BTC/USDT'
exchange = ccxt.binance()
ohlcv = exchange.fetch_ohlcv(symbol, '1d', limit=365)
df = pd.DataFrame(ohlcv, columns=['timestamp', 'open', 'high', 'low', 'close', 'volume'])
df['rsi'] = ta.momentum.RSIIndicator(df['close'], 14).rsi()

# Run backtest
results = backtest_strategy(df, rsi_strategy)

# Calculate metrics
equity = pd.Series(results['equity_curve'])
returns = equity.pct_change().dropna()

total_return = (results['final_value'] / results['initial_capital'] - 1) * 100
sharpe = np.sqrt(252) * returns.mean() / returns.std() if returns.std() > 0 else 0

running_max = equity.cummax()
drawdown = (equity - running_max) / running_max
max_drawdown = drawdown.min() * 100

# Trade stats
sell_trades = [t for t in results['trades'] if t['type'] == 'sell']
if sell_trades:
    wins = len([t for t in sell_trades if t['pnl'] > 0])
    win_rate = wins / len(sell_trades) * 100
    avg_win = np.mean([t['pnl'] for t in sell_trades if t['pnl'] > 0]) if wins > 0 else 0
    avg_loss = np.mean([t['pnl'] for t in sell_trades if t['pnl'] <= 0]) if wins < len(sell_trades) else 0
else:
    win_rate = avg_win = avg_loss = 0

print(f'📊 BACKTEST REPORT: RSI Strategy on {symbol}')
print('=' * 60)
print(f'Period: {len(df)} days')
print(f'Initial Capital: \${results[\"initial_capital\"]:,.2f}')
print(f'Final Value: \${results[\"final_value\"]:,.2f}')
print()
print('PERFORMANCE METRICS')
print('-' * 60)
print(f'Total Return: {total_return:+.2f}%')
print(f'Sharpe Ratio: {sharpe:.2f}')
print(f'Max Drawdown: {max_drawdown:.2f}%')
print()
print('TRADE STATISTICS')
print('-' * 60)
print(f'Total Trades: {len(sell_trades)}')
print(f'Win Rate: {win_rate:.1f}%')
print(f'Avg Win: {avg_win:+.2f}%')
print(f'Avg Loss: {avg_loss:.2f}%')
print(f'Profit Factor: {abs(avg_win/avg_loss) if avg_loss != 0 else \"N/A\":.2f}')
"
Compare Multiple Strategies
bash
python3 -c "
import ccxt
import ta
import pandas as pd
import numpy as np

# Load data
symbol = 'BTC/USDT'
exchange = ccxt.binance()
ohlcv = exchange.fetch_ohlcv(symbol, '1d', limit=365)
df = pd.DataFrame(ohlcv, columns=['timestamp', 'open', 'high', 'low', 'close', 'volume'])

# Calculate all indicators
df['rsi'] = ta.momentum.RSIIndicator(df['close'], 14).rsi()
df['ema_12'] = ta.trend.ema_indicator(df['close'], 12)
df['ema_26'] = ta.trend.ema_indicator(df['close'], 26)
bb = ta.volatility.BollingerBands(df['close'], 20, 2)
df['bb_lower'] = bb.bollinger_lband()
df['bb_upper'] = bb.bollinger_hband()

def calc_return(signal_series):
    returns = df['close'].pct_change()
    strategy_returns = signal_series.shift(1) * returns
    return ((1 + strategy_returns.fillna(0)).prod() - 1) * 100

# Strategy 1: RSI
rsi_signal = pd.Series(0, index=df.index)
rsi_signal[df['rsi'] < 30] = 1
rsi_signal[df['rsi'] > 70] = 0

# Strategy 2: EMA Crossover
ema_signal = pd.Series(0, index=df.index)
ema_signal[df['ema_12'] > df['ema_26']] = 1

# Strategy 3: Bollinger Bands
bb_signal = pd.Series(0, index=df.index)
bb_signal[df['close'] < df['bb_lower']] = 1
bb_signal[df['close'] > df['bb_upper']] = 0

# Buy and Hold
buy_hold = ((df['close'].iloc[-1] / df['close'].iloc[0]) - 1) * 100

print('📊 STRATEGY COMPARISON')
print('=' * 50)
print(f'Symbol: {symbol}')
print(f'Period: {len(df)} days')
print()
print('Returns:')
print(f'  RSI Strategy:     {calc_return(rsi_signal):+.2f}%')
print(f'  EMA Crossover:    {calc_return(ema_signal):+.2f}%')
print(f'  Bollinger Bands:  {calc_return(bb_signal):+.2f}%')
print(f'  Buy & Hold:       {buy_hold:+.2f}%')
"

Workflow

Backtesting Process
  1. Define Hypothesis - What pattern are you testing?
  2. Gather Data - At least 1 year of historical data
  3. Code Strategy - Clear entry/exit rules
  4. Run Backtest - Generate performance metrics
  5. Analyze Results - Look for overfitting
  6. Walk-Forward Test - Test on unseen data
  7. Paper Trade - Real-time validation
Key Metrics
MetricGoodBad
Total Return> Buy & Hold< 0%
Sharpe Ratio> 1.5< 0.5
Max Drawdown< 20%> 50%
Win Rate> 50%< 30%
Profit Factor> 1.5< 1.0
Avoiding Overfitting
  • Use out-of-sample testing
  • Keep strategy rules simple
  • Avoid curve-fitting to specific periods
  • Test on multiple assets
  • Be skeptical of "too good" results

© Signal-Execution-Labs, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file (scripts) in skills/backtester of Signal-Execution-Labs/forex-trading-ai-agent.

  • SKILL.md
  • scripts/backtest_runner.py

Open the folder on GitHubat commit b8a6047

Compare with similar skills

Backtester next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

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Questions about Backtester

What does Backtester do?

Backtest trading strategies with historical data. An agent skill from Signal-Execution-Labs/forex-trading-ai-agent. Backtester is an agent skill from Signal-Execution-Labs/forex-trading-ai-agent. Backtest trading strategies with historical data.

When should I use Backtester?

Backtester fits situations like: tasks that involve Trading and backtesting; tasks that involve OKRs and executive reporting.

How do I install Backtester in Claude Code?

Run `npx skills add Signal-Execution-Labs/forex-trading-ai-agent --skill backtester -a claude-code`. Or copy the skill folder (skills/backtester in Signal-Execution-Labs/forex-trading-ai-agent) into .claude/skills/backtester in your project. Claude Code loads it when a task matches its description.

How do I install Backtester in Codex?

Run `npx skills add Signal-Execution-Labs/forex-trading-ai-agent --skill backtester -a codex`. Or copy the skill folder (skills/backtester in Signal-Execution-Labs/forex-trading-ai-agent) into .agents/skills/backtester in your project. Codex loads it when a task matches its description.

Can I use Backtester in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add Signal-Execution-Labs/forex-trading-ai-agent --skill backtester -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/backtester, .gemini/skills/backtester, .github/skills/backtester and .opencode/skills/backtester in your project.

What does Backtester need to run?

Going by SKILL.md and its folder, Backtester needs Python for the scripts in its folder and the command-line tools its instructions call (python3). Our summary lists: Python 3.

Does Backtester access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Backtester safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.

What licence does Backtester use?

Backtester is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Backtester use?

About 2.7k tokens (SKILL.md is roughly 11k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Backtester?

Skills that share tags, products or a category with Backtester: Pine Backtester (TradersPost/pinescript-agents, 170 stars), Vectorbt (agiprolabs/claude-trading-skills, 410 stars), Stock Performance (OctagonAI/skills, 127 stars) and Trading As Business (agentii-ai/agentii-investment-intelligence, 207 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Backtester?

Signal-Execution-Labs (a GitHub organization) maintains it in Signal-Execution-Labs/forex-trading-ai-agent, which has 162 GitHub stars. The repository holds 11 skills in this directory. The repository was last updated on September 14, 2026.

Source: Signal-Execution-Labs/forex-trading-ai-agent on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.