Placeholder Messages are a powerful feature that allows you to inject messages into a prompt template. By using the placeholder message role, you can define placeholders within your prompt template that can be replaced with full messages at runtime. This complements our standard template variables feature, which allows you to insert simple values into your prompts. This is useful to inject conversation context.

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Creating Placeholder Messages

You can create Placeholder Messages either through the PromptLayer dashboard or programmatically using the templates.publish method. In the dashboard, simply create a new message with the role placeholder and provide the desired placeholder content. Placeholder Message

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Running a Template with Placeholders

Programmatically, you can include Placeholder Messages when publishing a prompt template: 
promptlayer_client.run(
    prompt_name="template-name",
    input_variables={
        "fill_in_message": [
            {
                "role": "user",
                "content": [{"type": "text", "text": "My age is 29"}],
            },
            {
                "role": "assistant",
                "content": [{"type": "text", "text": "What a wonderful age!"}],
            }
        ]
    },
)
Passed in messages must confirm to our prompt blueprint format.