Prompt Blocks

Reusable, parameterized prompt templates — defined once, called like any other task.

Defining a prompt

prompt summarize(text, style="professional"):
    """Summarize this in a {style} tone: {text}"""

let result = summarize("the quick brown fox")
show result

A prompt block's triple-quoted body is a template — {style} and {text} are filled in from the arguments, the same way an f-string works.

What it returns

Calling a prompt returns the interpolated template string itself — it doesn't call an AI provider on its own. That makes it composable with think:

prompt summarize(text):
    """Summarize this in one sentence: {text}"""

task get_summary(document):
    return think summarize(document)

This separation is deliberate: the prompt's wording lives in one place, versioned and reusable, while think stays the single place that actually talks to a model.

Default parameter values

prompt summarize(text, style="professional"):
    """Summarize this in a {style} tone: {text}"""

show summarize("hello world")                    # uses "professional"
show summarize("hello world", style="casual")    # overrides it