Trait ResourceProvider 

pub trait ResourceProvider: Send + Sync {
    // Required methods
    fn list_resources<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Result<Vec<ResourceDescriptor>, CapabilityError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
    fn read_resource<'life0, 'life1, 'life2, 'life3, 'async_trait>(
        &'life0 self,
        id: &'life1 ResourceId,
        ctx: &'life2 mut CapabilityContext<'life3>,
    ) -> Pin<Box<dyn Future<Output = Result<ResourceContents, CapabilityError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             'life3: 'async_trait;
}

A provider of named data resources that can be listed and read.

Implement this trait to expose data sources – files on disk, database rows, API responses – to the model. The agentkit MCP bridge uses this trait to surface MCP-server resources into the agentic loop.

Example

use agentkit_capabilities::{
    CapabilityContext, CapabilityError, ResourceContents,
    ResourceDescriptor, ResourceId, ResourceProvider,
};
use agentkit_core::{DataRef, MetadataMap};
use async_trait::async_trait;

struct StaticFile;

#[async_trait]
impl ResourceProvider for StaticFile {
    async fn list_resources(&self) -> Result<Vec<ResourceDescriptor>, CapabilityError> {
        Ok(vec![ResourceDescriptor {
            id: ResourceId::new("readme"),
            name: "README.md".into(),
            description: Some("Project readme".into()),
            mime_type: Some("text/markdown".into()),
            metadata: MetadataMap::new(),
        }])
    }

    async fn read_resource(
        &self,
        id: &ResourceId,
        _ctx: &mut CapabilityContext<'_>,
    ) -> Result<ResourceContents, CapabilityError> {
        if id.as_str() == "readme" {
            Ok(ResourceContents {
                data: DataRef::InlineText("# Hello".into()),
                metadata: MetadataMap::new(),
            })
        } else {
            Err(CapabilityError::Unavailable(format!(
                "unknown resource: {id}"
            )))
        }
    }
}

Required Methods

fn list_resources<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Vec<ResourceDescriptor>, CapabilityError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Lists all resources currently available from this provider.

Errors

Returns CapabilityError if the provider cannot enumerate its resources (e.g. a network timeout).

fn read_resource<'life0, 'life1, 'life2, 'life3, 'async_trait>( &'life0 self, id: &'life1 ResourceId, ctx: &'life2 mut CapabilityContext<'life3>, ) -> Pin<Box<dyn Future<Output = Result<ResourceContents, CapabilityError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, 'life3: 'async_trait,

Reads the contents of the resource identified by id.

Arguments

• id - The unique resource identifier, as returned in a ResourceDescriptor.
• ctx - The shared capability context for this turn.

Errors

Returns CapabilityError::Unavailable if the resource does not exist or CapabilityError::ExecutionFailed if reading fails.

Implementors