withMastra()

Wraps an AI SDK model with Mastra processors and/or memory.

Usage example

src/example.ts

import { openai } from '@ai-sdk/openai'
import { generateText } from 'ai'
import { withMastra } from '@mastra/ai-sdk'
import type { Processor } from '@mastra/core/processors'

const loggingProcessor: Processor<'logger'> = {
  id: 'logger',
  async processInput({ messages }) {
    console.log('Input:', messages.length, 'messages')
    return messages
  },
}

const model = withMastra(openai('gpt-5.4'), {
  inputProcessors: [loggingProcessor],
})

const { text } = await generateText({
  model,
  prompt: 'What is 2 + 2?',
})

Parameters

model:

LanguageModelV2 | LanguageModelV3

Any AI SDK v5 or v6 language model (e.g., openai('gpt-5.4'), anthropic('claude-opus-4-6')).

options?:

WithMastraOptions

Configuration object for processors and memory.

WithMastraOptions

inputProcessors?:

InputProcessor[]

Input processors to run before the LLM call.

outputProcessors?:

OutputProcessor[]

Output processors to run on the LLM response.

memory?:

WithMastraMemoryOptions

Memory configuration - enables automatic message history persistence.

WithMastraMemoryOptions

storage:

MemoryStorage

Memory storage domain for message persistence. Get it from a composite store using await storage.getStore('memory').

threadId:

string

Thread ID for conversation persistence.

resourceId?:

string

Resource ID (user/session identifier).

lastMessages?:

number | false

Number of recent messages to retrieve, or false to disable.

semanticRecall?:

WithMastraSemanticRecallOptions

Semantic recall configuration (RAG-based memory retrieval).

workingMemory?:

MemoryConfig['workingMemory']

Working memory configuration (persistent user data).

readOnly?:

boolean

Read-only mode - prevents saving new messages.

Returns

A wrapped model compatible with generateText, streamText, generateObject, and streamObject.

Streaming behavior

Output processors that implement processOutputResult run after the stream finishes. Consume the stream to completion to persist message history and semantic recall.