Answers to common questions.

What is Routecraft?

Routecraft is a developer-first automation and integration framework for building data processing pipelines using a fluent DSL.

What is the difference between a capability and a context?

A capability is a single data processing pipeline with a source, optional operations, and a destination. A context is the runtime environment that manages multiple capabilities, handles their lifecycle, and provides shared services like logging and storage.

Can capabilities communicate with each other?

Yes -- use the direct() adapter to pass data between capabilities:

// Producer
craft()
  .id('producer')
  .from(source)
  .to(direct('my-channel'))

// Consumer
craft()
  .id('consumer')
  .from(direct('my-channel', {}))
  .to(destination)

See Composing Capabilities for fan-out, dynamic routing, and schema validation at the channel boundary.

How do I handle errors?

• Capability isolation -- a failed capability does not affect others running in the same context
• Event subscription -- subscribe to the error event in craft.config.ts for centralized handling
• Input validation -- add a Zod schema to your source adapter (e.g. direct(), mcp()) to reject invalid data before any logic runs
• Filtering -- use .filter(fn) to drop exchanges that do not meet a condition

What adapters are available?

Built-in adapters include simple(), timer(), csv(), json(), file(), http(), direct(), log(), debug(), and more.

For the complete list with options and signatures, see the Adapters reference.

How do I create a custom adapter?

Implement the appropriate interface (Source, Destination, or Processor) and set an adapterId:

class MyAdapter implements Source<string> {
  readonly adapterId = 'my.custom.adapter'

  async subscribe(context, handler, controller, onReady?) {
    // emit exchanges by calling handler(value)
  }
}

See Creating adapters for full examples including factory functions and multi-role adapters.

How do I expose a capability as an MCP tool?

Use mcp() from @routecraft/ai as the source adapter and run the file with craft run. See Expose as MCP.