Enum Content 

pub enum Content {
    Text(TextContent),
    Image(ImageContent),
    Audio(AudioContent),
    ResourceLink(ResourceLink),
    Resource(EmbeddedResource),
}

Content block in MCP messages (ContentBlock per spec).

Used in CallToolResult.content and PromptMessage.content.

Per MCP 2025-11-25, the union is: TextContent | ImageContent | AudioContent | ResourceLink | EmbeddedResource

Variants

Text(TextContent)

Text content

Image(ImageContent)

Image content (base64 encoded)

Audio(AudioContent)

Audio content (base64 encoded)

ResourceLink(ResourceLink)

Resource link (reference to a resource without embedding)

Resource(EmbeddedResource)

Embedded resource content

Implementations

impl Content

pub fn text(text: impl Into<String>) -> Content

Create text content.

pub fn image(data: impl Into<String>, mime_type: impl Into<String>) -> Content

Create image content from base64 data.

pub fn audio(data: impl Into<String>, mime_type: impl Into<String>) -> Content

Create audio content from base64 data.

pub fn resource_link(resource: Resource) -> Content

Create a resource link.

pub fn resource(uri: impl Into<String>, text: impl Into<String>) -> Content

Create embedded resource content.

pub fn is_text(&self) -> bool

Check if this is text content.

pub fn as_text(&self) -> Option<&str>

Get the text if this is text content.

pub fn is_image(&self) -> bool

Check if this is image content.

pub fn is_audio(&self) -> bool

Check if this is audio content.

pub fn is_resource_link(&self) -> bool

Check if this is a resource link.

pub fn is_resource(&self) -> bool

Check if this is resource content.

pub fn with_annotations(self, annotations: Annotations) -> Content

Add annotations to this content.

Trait Implementations

impl Clone for Content

fn clone(&self) -> Content

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Content

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Content

fn default() -> Content

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Content

fn deserialize<__D>( __deserializer: __D, ) -> Result<Content, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl IntoToolResponse for Content

fn into_tool_response(self) -> CallToolResult

Convert this type into a CallToolResult

impl PartialEq for Content

fn eq(&self, other: &Content) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Content

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Content