Pine Script v6 Alerts: alertcondition(), alert(), and Reliable Triggers

• alertcondition(cond, title, message) declares alert-able conditions for indicators.
• alert(message) fires a one-off alert in code when the script is used in an alert.
• Strategies can trigger alerts when you set the alert on the strategy and select execution options.
• Alert frequency is set in the UI: once, once-per-bar, once-per-bar-close.

//@version=6
indicator("EMA Crossover Alerts", overlay=true)

fastLen = input.int(20, "Fast EMA")
slowLen = input.int(50, "Slow EMA")

emaFast = ta.ema(close, fastLen)
emaSlow = ta.ema(close, slowLen)

longCond = ta.crossover(emaFast, emaSlow)
shortCond = ta.crossunder(emaFast, emaSlow)

plot(emaFast, color=color.new(color.teal, 0))
plot(emaSlow, color=color.new(color.orange, 0))

// Declare alert-able conditions with templated message tokens
alertcondition(longCond, title="Bullish Cross", message="{{ticker}} {{interval}} Bullish cross @ {{close}}")
alertcondition(shortCond, title="Bearish Cross", message="{{ticker}} {{interval}} Bearish cross @ {{close}}")

// Optional: UI previews using plotshape
plotshape(longCond, title="Long", style=shape.triangleup, color=color.new(color.teal, 0), location=location.belowbar)
plotshape(shortCond, title="Short", style=shape.triangledown, color=color.new(color.orange, 0), location=location.abovebar)

Create the alert from the chart: “Add alert” → Condition: this indicator → choose title → set frequency. Messages can use TradingView placeholders like {{ticker}}, {{interval}}, {{close}}.

Strategies don’t use alertcondition(). Instead, you set alerts on the strategy instance and let entries/exits generate signals. For webhook workflows, encode order side/size in the message template.

//@version=6
strategy("Strategy Alerts Template", overlay=true)

long = ta.crossover(ta.ema(close, 20), ta.ema(close, 50))
short = ta.crossunder(ta.ema(close, 20), ta.ema(close, 50))

if long
    strategy.entry("L", strategy.long)
if short
    strategy.entry("S", strategy.short)

// In the alert dialog for this strategy, set the webhook URL and a JSON message template
// Example JSON: {"symbol":"{{ticker}}","tf":"{{interval}}","side":"{{strategy.order.action}}","price":"{{close}}"}

• Once-per-bar-close is the safest: no intra-bar flicker; signal evaluated on the final bar state.
• Once-per-bar triggers on the first time the condition becomes true during a bar; can fire earlier and then reverse.
• For MTF filters, prefer bar-close alerts or explicit barstate.isconfirmed gating to avoid repaint-like behavior.

• Use request.security() with barmerge.lookahead_off and gate actions on confirmed HTF bars.
• Label and plot the HTF state on your LTF to visually verify timing before enabling alerts.
• Avoid conflicting frequency settings; prefer bar-close when in doubt.

Deep dive: MTF Strategy Design andRepaint Pitfalls.

alert() emits a message immediately from code when the script is attached to an active alert. Useful for multi-signal payloads or complex routing. Avoid spamming by guarding with edge detection.

//@version=6
indicator("Custom Alert() Example", overlay=false)

cond = ta.crossover(ta.rsi(close, 14), 50)
fired = ta.barssince(cond) == 0

if fired
    alert("RSI crossed 50 on {{ticker}}/{{interval}} @ {{close}}")

• Validate visually with plotshape() where alerts should occur.
• Use bar replay to confirm the alert would have fired at the intended bar timing.
• Send alerts to a test webhook endpoint to inspect payloads before going live.