Vercel AI SDK

What is supported

The AI SDK (ai) 6 and later. Onecortex recognises an agent object, such as a ToolLoopAgent, and streams it. A bare streamText call is not an agent: wrap it in a function, as on A TypeScript function.

A complete agent

agent.yml

apiVersion: v1
runtime: node22
entrypoint: agent.ts#agent
dependencies: package.json

package.json

{
  "type": "module",
  "dependencies": {
    "@ai-sdk/openai": "^3.0.0",
    "ai": "^7.0.0",
    "zod": "^4.0.0"
  }
}

agent.ts

import { openai } from '@ai-sdk/openai'
import { ToolLoopAgent, tool } from 'ai'
import { z } from 'zod'

// Reads OPENAI_API_KEY, which you add as a secret on the agent's Config tab.
export const agent = new ToolLoopAgent({
  model: openai('gpt-5'),
  instructions: 'Count the words in what the user says, then answer.',
  tools: {
    wordCount: tool({
      description: 'Counts the words in a piece of text.',
      inputSchema: z.object({ text: z.string() }),
      execute: async ({ text }) => ({ words: text.split(/\s+/).filter(Boolean).length }),
    }),
  },
})

Add OPENAI_API_KEY as a secret on the agent’s Config tab, then deploy. Any model works: this one is an example. See Configuration and secrets.

A complete Vercel AI SDK example

meeting-scheduler: A ToolLoopAgent that checks a calendar, then holds a slot: two tool calls in one run. It runs with no model key.

The prompt and the reply

The prompt is the agent’s input. The reply is its streamed text.

Events it reports

Events	From
`text`	The streamed text
`tool_call_start`, `tool_call_args`, `tool_call_end`	Each tool call, streamed as it forms
`tool_result`	Each tool’s output, with `isError` when it failed
`done` or `error`	The end of the run: always exactly one

See Streaming and events.

The caller’s fields

The AI SDK has no per call slot for extra data, so the caller’s fields do not reach an agent object. To use them, export a function that reads them and builds the call:

export async function handler(prompt: string, { request }: { request: { params: Record<string, unknown> } }) {
  const tone = String(request.params['tone'] ?? 'plain')
  const result = await agent.generate({ prompt: `Answer in a ${tone} tone: ${prompt}` })
  return result.text
}

Known limits

The caller’s fields do not reach an agent object; use a function wrapper.

Troubleshooting

You see	Do this
`Onecortex could not determine how to invoke the object at your entrypoint`	The export is not an agent object. Export the `ToolLoopAgent`, or a function.

Get started

Build your agent

Frameworks

Deploy

Call your agent

Observe

Production

Organizations

Resources

What is supported

A complete agent

A complete Vercel AI SDK example

The prompt and the reply

Events it reports

The caller’s fields

Known limits

Troubleshooting

​What is supported

​A complete agent

A complete Vercel AI SDK example

​The prompt and the reply

​Events it reports

​The caller’s fields

​Known limits

​Troubleshooting

What is supported

A complete agent

The prompt and the reply

Events it reports

The caller’s fields

Known limits

Troubleshooting