Installation¶

The plugin is installed by adding it to your Claude Code settings file.

Prerequisites¶

Claude Code installed and configured
A GitHub account (the plugin is hosted on GitHub)

Add the plugin¶

Open (or create) ~/.claude/settings.json and add the following:

{
  "enabledPlugins": {
    "spec-driven@spec-driven": true
  },
  "extraKnownMarketplaces": {
    "spec-driven": {
      "source": {
        "source": "url",
        "url": "https://github.com/Habib0x0/spec-driven-plugin.git"
      }
    }
  }
}

Restart Claude Code after saving the file.

Verify the installation¶

After restarting, type /spec in a Claude Code session. If the plugin is installed correctly, you will see the spec command activate.

Codex¶

The plugin also works with Codex via the manifest at .codex-plugin/plugin.json.

Install in Codex¶

codex plugin marketplace add Habib0x0/spec-driven-plugin

Command Syntax¶

Codex commands use $ prefix instead of /:

Claude Code	Codex
`/spec <name>`	`$spec <name>`
`/spec-brainstorm`	`$spec-brainstorm`
`/spec-bugfix <name>`	`$spec-bugfix <name>`
`/spec-status`	`$spec-status`
`/spec-exec`	`$spec-exec`
`/spec-loop`	`$spec-loop`

Usage in Codex¶

Invoke the skill by typing one of its default prompts:

Prompt	Action
`Create a spec for this feature`	Start a new spec workflow
`Validate the current spec`	Run validation on the active spec
`Break this design into tasks`	Regenerate tasks from the design doc

You can also reference the skill by its display name, e.g. Use Spec Driven to plan user authentication.

Under Codex, spec files are written to .codex/specs/<feature-name>/.

Plan Mode vs Build Mode¶

Codex supports two execution modes. The plugin works in both:

Plan Mode (codex --plan)

The agent generates the full spec content (requirements, design, tasks)
Codex presents it as a plan for review — no files are written yet
Review the spec, then approve to apply it in build mode
Use this when you want to see what the spec would look like before committing

Build Mode (codex default)

The agent generates and writes spec files directly to .codex/specs/
Implementation scripts (spec-exec.sh, spec-loop.sh) must be run from your terminal, not inside Codex
Use this when you want the spec created immediately and are ready to implement

Key differences from Claude Code:

Feature	Claude Code	Codex
Spec generation	Writes files directly	Writes files in build mode; plans in plan mode
Task sync	Syncs to Claude Code todo system	No native todo sync; tasks live in `tasks.md`
Execution	`/spec-exec` and `/spec-loop` slash commands	Run `spec-exec.sh` / `spec-loop.sh` from terminal
Spec directory	`.claude/specs/`	`.codex/specs/`

Next steps¶

Follow the Quick start to create your first spec
Read Concepts to understand how EARS notation and task lifecycle work