Skip to main content

Build Dex applications with AI

Dex Developer is the official coding-agent skill for Dex. It helps Codex, Claude Code, Cursor, and other Agent Skills clients work through the public Dex programming model in Python, Go, Java, TypeScript, and Rust.

The skill guides application development. Dex Server, Workers, and SuperAgent do not load it at runtime.

What the skill helps with​

  • Choose a design pattern for the application's durability and coordination needs.
  • Model Flows, Steps, transitions, and failure paths before implementation.
  • Choose Attributes, Channels, Streams, RPCs, Timers, and SubFlows.
  • Use version-matched SDK APIs and runnable examples.
  • Test Worker replacement, retries, durable waits, and recovery.
  • Diagnose Flow failures through read-only evidence before recovery actions.

The source and releases are maintained in superdurable/skill-dex-developer.

Install for Codex​

Add the Super Durable marketplace and install the Dex plugin:

codex plugin marketplace add superdurable/skill-dex-developer
codex plugin add dex@superdurable

Start a new task, then invoke the skill explicitly when needed:

$dex-developer Design a reliable Dex Flow for this application.

Codex can also select the skill automatically for Dex application work.

Install for Claude Code​

Run these commands inside Claude Code:

/plugin marketplace add superdurable/skill-dex-developer
/plugin install dex@superdurable
/reload-plugins

Invoke the skill as follows:

/dex:dex-developer

Install for Cursor​

The Dex plugin follows the portable Agent Plugins standard supported by Cursor. Before it is listed in the public Cursor Marketplace, a team can import the GitHub repository into a team marketplace. An individual can install the skill directly:

npx skills add superdurable/skill-dex-developer --skill dex-developer

Invoke the installed skill manually when needed:

/dex-developer

Cursor can also select the skill automatically from the task context.

Keep the skill current​

Agents use an installed or cached copy. They do not fetch the latest GitHub content for every prompt, and an active task keeps the version loaded when that task started.

  • In Codex, upgrade the Super Durable marketplace, reinstall the Dex plugin, and start a new task.
  • In Claude Code, update the marketplace and reload plugins. Third-party marketplace auto-update can be enabled in the plugin manager.
  • In Cursor, refresh or reinstall the plugin. Team marketplaces can enable Auto Refresh. Reload the window after changing a local plugin.
  • For a direct Agent Skills installation, rerun the installation command.

The skill release version is separate from the Dex SDK version. The skill tells the agent to inspect the SDK installed by the application and use matching runnable examples before choosing exact APIs.

Trust and permissions​

Install agent extensions only from sources you trust. The Dex plugin contains guidance files only. It declares no MCP server, hooks, credentials, or application runtime code. Recovery actions that mutate a running Flow still require explicit authorization.