AI Credits, Plan Limits & Quota Architecture

In PostBrix, AI credits are assigned to the User Account of the workspace owner. This design provides seamless team collaboration without complex per-user quota management:

• Single Shared Pool: All team members, editors, and collaborators working within a workspace draw from the workspace owner's central credit pool.
• Unified Billing: Purchasing or upgrading a subscription plan directly increases the account credit balance available to all projects within owned workspaces.
• Owner Governance: Account owners can track real-time credit consumption across all active team members in Settings → Billing & AI Credits.

Every PostBrix account includes an AI credit allowance tailored to its subscription tier:

Note: Paid plan credits reset automatically on your monthly subscription renewal date. Unused monthly credits do not roll over to subsequent billing cycles.

Different AI operations consume different amounts of computational infrastructure, large language model (LLM) tokens, and image processing pipeline cycles. To maintain fair usage, PostBrix categorizes AI features into three credit cost tiers:

1 Credit — Lightweight Text & Metadata AI

Operations that process focused text snippets or lightweight prompt transformations:

• Text Refinement (improve-text): Rephrasing, shortening, expanding, tone adjustment (Professional, Friendly, Urgent), and grammar fixes on existing text blocks.
• Subject & Preheader Generation (generate-subject): Creating conversion-optimized subject lines and preview text snippets.
• Multi-Language Translation (translate): Translating email copy into 30+ target languages while preserving Handlebars tags.
• Image Metadata & Alt Text (generate-metadata): Generating accessibility alt text and image descriptions.

2 Credits — Generative Templates, Image Synthesis & Smart Dispatch

Operations that synthesize complete layout block trees, render AI images, or process smart send workflows:

• Prompt-to-Template Generation (generate-template): Synthesizing complete multi-section MJML email layouts from a text prompt.
• AI Image Generation (generate-image): Creating custom high-resolution marketing banners and illustrations from text descriptions.
• Image Editing & Inpainting (edit-image): Magic erasure, background modification, and canvas extension.
• Sticker & Badge Studio (generate-sticker): Generating transparent vector-style promotional badges and callout graphics.
• Image Vision Analysis (analyze-image): Analyzing image contrast, legibility, and visual layout hierarchy.
• AI Direct Send (ai-direct-send): Context-aware automated email dispatch and rendering optimization.

3 Credits — Multimodal Vision Image-to-Template Conversion

Converting an image (screenshot, Figma design, competitor newsletter, or physical mockup) into a fully editable, responsive MJML email template (image-to-template).

Why Image-to-Template Costs 3 Credits:

1. Multimodal Vision Tokens: Processes high-resolution visual inputs through multi-modal vision models to identify structural grids, column splits, margins, and content regions.
2. OCR & Typography Extraction: Extracts all visible text copy, font hierarchy, alignment, and CTA buttons from the image.
3. Color Palette Detection: Samples exact background, text, and accent hex codes to reconstruct your brand palette.
4. 12-Stage MJML Structural Healing: Runs a 12-stage validation and healing engine that translates raw visual bounding boxes into valid, email-client-tested MJML block trees (preventing broken tables in Outlook).

PostBrix protects your account against double-billing and technical failures through a 2-phase transactional credit contract:

1. Atomic Pre-Deduction: Before any LLM inference request is dispatched, PostBrix performs an atomic SQL conditional deduction (UPDATE UserCreditAccount SET balance = balance - cost WHERE balance >= cost). If your balance is insufficient, the operation is blocked immediately without making expensive API calls.
2. Automatic Failure Refund: If upstream AI inference fails (e.g. network timeout, rate limit, or invalid output format) or if MJML compilation fails validation, PostBrix executes an immediate automatic refund transaction. The deducted credits are instantly returned to your balance with zero manual intervention required.

Account owners and workspace members can monitor AI credit usage in real time:

• Navigate to Settings → Billing & AI Credits.
• View your current balance, monthly plan allowance, and billing cycle renewal date.
• Inspect detailed credit transaction logs listing the feature used (e.g., image-to-template), credit cost (-3), timestamp, and initiating team member.