Package akka.javasdk.agent

Interface MessageContent

All Known Subinterfaces:

MessageContent.DataMessageContent, MessageContent.ImageDataMessageContent, MessageContent.LoadableMessageContent, MessageContent.PdfDataMessageContent

All Known Implementing Classes:

MessageContent.ImageBytesMessageContent, MessageContent.ImageUrlMessageContent, MessageContent.PdfBytesMessageContent, MessageContent.PdfUrlMessageContent, MessageContent.TextMessageContent

public sealed interface MessageContent
permits MessageContent.LoadableMessageContent, MessageContent.DataMessageContent, MessageContent.TextMessageContent

Represents a piece of content within a multimodal message to an AI model.

Message content can be text, images, or PDFs, allowing agents to send multimodal inputs.

See Also:

• UserMessage

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	MessageContent.DataMessageContent	Inline content already loaded as bytes.
static final record	MessageContent.ImageBytesMessageContent	Image content carried as inline bytes, for returning binary media from a @FunctionTool.
static interface	MessageContent.ImageDataMessageContent	Image content carried as inline bytes.
static final record	MessageContent.ImageMessageContent	Factory methods for creating image message content.
static final record	MessageContent.ImageUrlMessageContent	Image content within a user message, referenced by URI.
static interface	MessageContent.LoadableMessageContent
static final record	MessageContent.PdfBytesMessageContent	PDF content carried as inline bytes, for returning binary media from a @FunctionTool.
static interface	MessageContent.PdfDataMessageContent	PDF content carried as inline bytes.
static final record	MessageContent.PdfMessageContent	Factory methods for creating PDF message content.
static final record	MessageContent.PdfUrlMessageContent	PDF content within a user message, referenced by URI.
static final record	MessageContent.TextMessageContent	Text content within a user message.

Method Summary

Static Methods

Modifier and Type	Method	Description
static void	requireSendableAsInput(Iterable<? extends MessageContent> contents)	Validates that every content item may be sent to the model as input.

Method Details

requireSendableAsInput

static void requireSendableAsInput(Iterable<? extends MessageContent> contents)

Validates that every content item may be sent to the model as input.

Inline byte payloads (MessageContent.DataMessageContent) are only supported as a @FunctionTool return value; as model input, images and PDFs must be referenced by URI. This is a deliberate, permanent constraint: a user message can travel across the cluster, so it must stay reference-based (a URI) rather than carry potentially large inline bytes.

Throws:

IllegalArgumentException - if any item carries inline bytes