Workday documents four groups of AI developer tooling for Extend: Developer Agent, which builds apps and agents from a plain-language prompt; three Developer Copilot assistants for Extend apps, APIs and Orchestrate; Agent-Ready Tools, the library of tools an AI agent calls to work with Workday data; and the Workday Developer CLI (WDCLI), which Developer Agent uses when it runs in your editor. Developer Copilot is part of the Extend AI package and not of Extend Core, and Workday's product page offers Developer Agent through Extend Professional, which Workday's changelog says is now called Extend AI.

Everything below comes from Workday's own Extend documentation, and nothing it does not document is listed.

Which Extend package includes which tool?

Workday sells Extend in two packages, Extend Core and Extend AI. Its packages page lists Developer Copilot under Workday AI with a check mark for Extend AI only. The same group of rows also lists Workday AI Gateway, Workday Extend AWS Integration and AI Widgets for Extend AI. Those are features you put into an app and not tools for the developer, so they are not covered here.

Tool What it does Where it runs Who gets it
Developer Agent Builds and changes apps, agents and orchestrations from a prompt, and checks its own work Developer Site (App Builder); Claude Code, VS Code, Cursor, Google Antigravity Offered through Extend Professional, now Extend AI; priced in Flex Credits
Developer Copilot for Extend Apps Answers questions from Workday's documentation and generates components and scripts Search box, chat window and App Builder on the Developer Site Extend AI customers
Developer Copilot for APIs Finds and compares REST, SOAP and Graph APIs from a description Developer Site Extend AI customers
Developer Copilot for Orchestrate Generates and explains orchestrations Orchestration Builder Extend AI customers in North America and EMEA only
Agent-Ready Tools Pre-built tools an AI agent calls to read and act on Workday data A Workday custom agent, or an external agent registered in Agent System of Record Callable by any registered agent; building custom agents needs Flex Credits
WDCLI Uploads, downloads, deploys and promotes apps from a terminal Your computer All Developer Site users, though some commands need the Extend SKU

Developer Agent

Developer Agent is the one Workday calls an agentic AI development assistant. From a single prompt it can build a whole Extend app or Agent app, including business objects and security domains, change an existing app, validate its own output and fix the errors, and generate mock data to fill views. It also generates WQL and Graph queries, PMD pages and scripts, reviews code on request (for example "Review my code"), and writes the skill files that register an agent in Agent System of Record.

You use it in two places. In App Builder on the Developer Site it proposes changes in Draft Mode, and you preview them in App Preview before you apply them. In an editor, the Developer Agent Extension works in Claude Code, Cursor, VS Code and Google Antigravity, and needs the WDCLI installed alongside it. You sign in to both once; they share a session. To work on an existing app in your editor you pull it with the WDCLI first.

Two limits are in Workday's own documentation. It needs a connection to a tenant to generate Graph queries and mutations, to preview business objects, to generate WQL, and to generate agent skills (because that is how it learns which Agent-Ready Tools the tenant has). And it does not configure security: after you deploy an app or agent, you set up its security in the tenant. Workday also tells you to keep personally identifiable information out of prompts.

The product page says Developer Agent uses Flex Credits-based pricing and tells customers to contact their Workday account team for access. How much it costs is in your contract, not in the documentation.

The three Developer Copilots

Developer Copilot answers questions and generates pieces of an app. Workday's documentation does not describe it running a build-and-validate loop the way it describes Developer Agent doing.

  • For Extend Apps. The chat window and the Developer Site search box summarize Workday's documentation and its REST, SOAP and Graph API specifications. In App Builder it generates Graph queries and mutations, example pages with supported widgets, pages that read and update data through Graph, business objects, attachments and security domains.
  • For APIs. You describe a use case and it suggests APIs, lets you compare up to three side by side with a preview of the request and response, and links to the REST, SOAP or Graph API Explorer.
  • For Orchestrate. In Edit mode it builds orchestrations from a description, working on a non-live copy that you review and accept; in Ask mode it inspects an orchestration and answers questions from the Developer Site and Administrator Guide. Workday calls it experimental and says you must always review its work. It cannot create some components, among them Trigger Integration and the Amazon S3 steps, and it does not work with Studio or EIB integrations.

Agent-Ready Tools

These are not an assistant for you. They are what the agents you build, or any agent you register, call to reach Workday. Workday describes them as interfaces built for AI use, with flattened schemas and metadata that help an agent pick the right tool, secured with delegate authorization. Workday's tools explorer lists them as Basic (read-only), Advanced (write-only) or Prompt (read-only tools some Advanced ones need). You can also search them through the Agent System of Record's Agent Resource Search API, which needs the Setup: Agents domain.

Workday also states that they are for AI agent use and not for hard-coded integrations, and that it changes them continuously without versions: tools can be renamed and their schemas restructured, with the explorer updated weekly. Do not build a fixed integration on one. The explainer on Agent-Ready Tools covers how to scope them, and building a custom agent shows where they fit.

The Workday Developer CLI

The WDCLI is not an AI tool by itself. Workday documents it for scripting: signing in, uploading and downloading apps, deploying them to tenants and promoting them. It matters here because the Developer Agent Extension depends on it, and because anything that can run a command in a terminal, including a general coding assistant, can use it the same way. Workday notes that it is available to all Developer Site users, but not every command completes without the Extend SKU, and that a system user account cannot do tenant-level operations such as deploying an app. See the WDCLI guide.

Third-party assistants and kiweely

Workday documents two places where assistants it does not make plug in. Developer Agent runs inside Claude Code, Cursor, VS Code and Google Antigravity. And an external agent on a platform such as Claude, Cursor, Copilot Studio or Google Agentspace can call Agent-Ready Tools once it is registered in Agent System of Record and its tools are set. Workday documents no other third-party route, so a general coding assistant working on Extend files does so with the WDCLI and your own instructions, without Developer Agent or Workday's tool library unless you set those up.

kiweely is a desktop app that does the same Extend work from outside Workday's tools. It connects to a tenant, designs and validates Extend apps against Workday's own validation, deploys to Development after you approve, and tests the result in a browser as different users. It asks before it changes anything.

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