RC2_EXIT_NO_QTY

Exit verbs (sell, buy_to_cover) require an explicit quantity.

What it means

Exit verbs aren’t auto-sized by the strategy’s sizing model — they need to know exactly how much to exit. The transpiler refuses an exit call without a quantity, even when the intent looks obvious.

Why it happens

class Bad(Strategy):
    trade = Symbol()
    sizing = FixedCapital()

    def execute(self):
        if self.trade.is_long:
            self.sell(self.trade, reason="Exit")   # ❌ — no quantity given

You probably meant “sell everything I hold.” The transpiler doesn’t infer that — it makes you say it.

How to fix it

Pass the quantity as the second positional argument. self.trade.position is “everything I hold”:

class Good(Strategy):
    trade = Symbol()
    sizing = FixedCapital()

    def execute(self):
        sma = SMA(20, on=self.trade)

        if self.trade.is_flat:
            self.buy(self.trade)

        if self.trade.is_long:
            self.sell(self.trade, self.trade.position, stop=sma.value)   # ✅ full exit

Other common forms — all of them positional:

class ExitForms(Strategy):
    trade = Symbol()
    sizing = FixedCapital()

    def execute(self):
        if self.trade.is_long:
            self.sell(self.trade, self.trade.position / 2)      # exit half
        if self.trade.is_short:
            self.buy_to_cover(self.trade, self.trade.position)  # close a short

Why no qty= kwarg?

Quantity for exits is always positional: the second argument of sell / buy_to_cover is how much of the position to close, and it is never a keyword. qty= and percent= on an exit verb are RC2_EXIT_NO_KWARGS.

Note the order the two checks run in: the missing-positional test comes first, so self.sell(self.trade, qty=100) — a kwarg with no positional at all — reports this code, not RC2_EXIT_NO_KWARGS. You see RC2_EXIT_NO_KWARGS only when the positional quantity is present and a forbidden kwarg is passed alongside it.

Related

• Order Verbs
• Position Helpers