Print a pretty representation of the prompt.
A list of the names of the variables whose values are required as inputs to the
A list of the names of the variables for placeholder or MessagePlaceholder that
A dictionary of the types of the variables the prompt template expects.
How to parse the output of calling an LLM on this formatted prompt.
A dictionary of the partial variables the prompt template carries.
Metadata to be used for tracing.
Tags to be used for tracing.
Return the output type of the prompt.
The name of the Runnable. Used for debugging and tracing.
Input type.
Output Type.
The type of input this Runnable accepts specified as a Pydantic model.
Output schema.
List configurable fields for this Runnable.
Prompt template for a language model.
A prompt template consists of a string template. It accepts a set of parameters from the user that can be used to generate a prompt for a language model.
The template can be formatted using either f-strings (default), jinja2, or mustache syntax.
Prefer using template_format='f-string' instead of template_format='jinja2',
or make sure to NEVER accept jinja2 templates from untrusted sources as they may
lead to arbitrary Python code execution.
As of LangChain 0.0.329, Jinja2 templates will be rendered using Jinja2's SandboxedEnvironment by default. This sand-boxing should be treated as a best-effort approach rather than a guarantee of security, as it is an opt-out rather than opt-in approach.
Despite the sandboxing, we recommend to never use jinja2 templates from untrusted sources.
Example:
from langchain_core.prompts import PromptTemplate
# Instantiation using from_template (recommended)
prompt = PromptTemplate.from_template("Say {foo}")
prompt.format(foo="bar")
# Instantiation using initializer
prompt = PromptTemplate(template="Say {foo}")Create PromptValue.
The type of config this Runnable accepts specified as a Pydantic model.