Set up your first Agent

Connect a Model, create an Agent, and choose execution permissions.

Setup connects a Model, creates an Agent, and selects execution permissions. It runs automatically when no default Agent is configured or the selected Agent has no Model. To run it again, quit the TUI and use:

Terminal
a13n-harness-ui setup

The TUI has no /setup command. Explicit setup returns to your shell after saving; first-use setup then opens the TUI composer.

1. Connect a Model

Choose a ChatGPT, Codex, Grok, or GitHub Copilot subscription, or an API-key connection.

ConnectionWhat you provideWhere credentials live
ChatGPT subscriptionSign-in and the complete callback URLHarness UI data root (auth.json)
Codex subscriptionCompatible loginShared Codex account store
Grok subscriptionCompatible loginShared Grok account store
GitHub Copilot subscriptionDevice login or an existing Copilot CLI loginHarness UI data root (oauth/copilot.json) or the Copilot CLI store
API keyProvider/protocol, model ID, and key referenceAn environment variable or Harness UI's local key store

Existing compatible subscription logins are detected and can be reused. If login is missing, setup offers to sign in (device code, local browser, or callback URL, as the provider supports), to check again after an external a13n-harness-ui login <provider>, or to configure without signing in. The TUI has no /login command. Malformed or unsupported stores receive repair guidance, not automatic replacement.

For API keys, setup offers a hidden key field. You can also supply env:OPENAI_API_KEY or key:key-primary. Never paste a key into the TUI composer. A newly entered key is saved immediately to the separate local key store, not to Model YAML.

Models and authentication covers login methods, stored keys, and account locations.

2. Select the model and settings

Choose from the installed starter catalog or enter a case-sensitive API model ID. The catalog is bundled guidance, not a live entitlement or availability check. Existing Model resources retain their settings rather than being silently migrated to new defaults.

For a new Codex connection, setup also offers Fast or Standard service. Fast requests priority; it may consume more quota and does not guarantee speed. Use /fast for a temporary change or edit the Model for a permanent one.

Native image/audio/video declarations are saved for known model routes. They tell Harness which inputs to send; they do not add a modality that the actual endpoint lacks. Verify custom endpoints before copying declarations.

See Model settings, context budgets, and Fast mode.

3. Choose execution permissions

  • Full Control: commands run with your host account's filesystem and network authority. No Envd runtime is required.
  • Sandbox: setup checks local isolation prerequisites before saving. Failure does not fall back to Full Control. Built-in Windows execution supports Full Control only.

Your selection saves configuration without an additional confirmation step. Read execution permissions before choosing.

The TUI uses its launch directory as the working directory; on the first prompt it selects or creates a single-root Project for that directory. Setup does not require a Project file or create a default project-local resource.

Advanced setup

Terminal
a13n-harness-ui setup --advanced

Advanced setup exposes optional context, reasoning, shell-review, subagent, and instruction choices. Normal setup supplies starter values; these are still editable YAML, not hidden application state.

Normal setup includes three built-in child roles and, if absent, enables security.shell_review at the extra_high threshold. It uses a configured Model to review shell launches and asks for approval when flagged. Existing review settings are preserved. This review is not isolation and does not inspect every command; see shell review configuration for the exact policy.

Built-in subagents inherit the parent Model. Advanced setup offers all or none; edit subagents.include to choose individual roles. External Codex/Claude Code subagent import is a separate /import workflow, not part of setup.

Add another connection or Agent

Terminal
a13n-harness-ui add model
a13n-harness-ui add agent

add model creates a reusable Model and offers a separate Agent flow. add agent lets you reuse a Model or create a new one, then name the Agent. Reuse references the existing Model without copying or editing it. Repeated names allocate separate identities; existing defaults and conversations remain unchanged.

Use /agent to switch the complete Agent. Use /model to select a configured Model for this Project while keeping the current Agent's instructions and tools; /model default clears that choice.

Cancel or recover setup

Use Up/Down and Enter, or type option numbers. Esc goes back; Ctrl+C or Ctrl+D cancels. Cancelling first-use setup returns to the shell without opening the TUI composer.

A completed login or saved key remains even if setup is cancelled. If publishing several files fails, inspect the completed paths shown in the error before retrying. Setup creates no recovery files. A .a13n-harness-ui-setup-recovery-* directory from an older release is left untouched; review its content before you delete it.

Inspect what was saved

The generated root configuration explicitly enables WebUI Sidekick:

YAML
webui:
  sidekick: {}

This does not start work automatically. Set sidekick: null or choose Settings → General → Sidekick → Disabled to turn off the preference. Repeating setup preserves an explicit opt-out or custom Agent/Model selections.

Terminal
a13n-harness-ui config path
a13n-harness-ui config show --format json
a13n-harness-ui config validate

Continue with configuration recipes or the starter root document.

On this page