> ## Documentation Index > Fetch the complete documentation index at: https://docs.fullotto.app/llms.txt > Use this file to discover all available pages before exploring further. # Billing > How Otto's prepaid credits and usage-based charges work. Otto uses prepaid workspace credits. Each review or workflow is charged for the work it actually performed, based on verified usage. ## Getting started When you create a workspace, Otto asks for a card. It verifies the card with Stripe (no charge) and adds a **\$10 welcome credit** so your first reviews can run. Auto-reload is on by default, and you can change it before you save the card. ## Adding funds 1. Go to **Settings → Billing**. 2. Click **Add Funds**. 3. Choose a preset amount or enter your own. 4. Pay through Stripe. The Add Funds dialog Unused credits never expire. ## How charges work * **Only verified usage is billed.** Estimated prices are shown for previews only and are never billed. * **Review charges are grouped by pull request**, so you can see what each PR cost. * **Depth affects cost.** Deeper [review depths](/configuration/review-depth) cost more; use `otto.yml` to spend depth where it matters and [ignore](/configuration/ignoring-files) files that don't need review. * **Fractional cents are kept** and carried into later charges instead of rounding each request up. * **Unverified usage stays pending** until it can be reconciled. Otto never guesses a cost. | Label | Meaning | | - | - | | `pending` | Usage hasn't been fully verified or settled yet. | | `charged` | Verified usage was charged to your balance. | | `waived` | Usage was recorded but not billed, such as a failed workflow attempt. | ## What you're not charged for * Workflow attempts that fail terminally, and failed recovery attempts. A failed attempt stays waived even if a later retry succeeds. * [Skipped reviews](/configuration/skipping-reviews) and PRs too large to review automatically. Recoverable tool errors and negative review findings aren't failures; a review that requests changes is a successful review. If you cancel a workflow, usage already consumed before the cancellation is billed. ## When automation pauses Otto pauses automation for a workspace when: * It runs out of credits, or * 3 workflow attempts in a row fail terminally, or * Failed attempts absorb \$5.00 of cost within 24 hours. Successful work resets the failure streak. Add funds to resume after running out of credits; contact support if automation is paused for failures. ## Viewing usage **Settings → Billing** shows usage by date, model, workflow, and run, including token details when available and each record's billing label. See [Usage](/billing/usage). This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.