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Before you start

  • A PlatformDTC account with access to the store whose theme you want to build.
  • The Codex CLI installed.

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1. Add the server

Or add it to ~/.codex/config.toml yourself:

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2. Sign in

Codex registers itself with PlatformDTC (dynamic client registration — there is no client ID to copy) and opens your browser:
1

Sign in to PlatformDTC

Sign in with your PlatformDTC account if you are not already.
2

Choose a store and permissions

The consent screen names the client asking for access and the permissions it requests. Pick the store, untick any permission you do not want to grant, and approve.
3

Return to Codex

The login completes in your terminal. Codex stores the tokens and refreshes them.

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3. Build

Start codex and describe the change:
The agent creates a development theme, reads the manifest and the template, writes the change, runs check_theme and returns a preview_theme link. The theme also opens in the dashboard editor with the change applied.

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4. Publish

Ask Codex to publish. By default the publish waits for your approval — the tool returns pending_approval until you approve it in Settings → Developer → Build with your agent. See Scopes and approvals.

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Headless use (CI)

For automation with no browser, you can use a static sq_agt_* key with the theme scopes instead of OAuth. Put it in an environment variable and point Codex at it:
Create the key under Agents → Access → API keys with only the scopes the job needs. A static key does not expire on a timer — revoke it when the job no longer needs it.