n8n Detention Claim Approval Workflow: OpenAI, Gmail & TMS

Automatically calculate, draft, approve, and commit carrier detention claims—using n8n, OpenAI, Gmail, and your TMS API

This n8n Detention Claim Approval Workflow captures carrier detention submissions from an n8n Form, calculates billable detention with free-time and tier caps, drafts a settlement offer with OpenAI, routes approvals through Gmail, and—once approved—posts the charge to your TMS accessorial-charge API while logging outcomes in Google Sheets.

What this workflow does

• Receives a carrier submission via an n8n Form including load details, timestamps, carrier tier, and the contracted detention rate.
• Normalizes input and calculates billable detention: applies 2 hours of free time, uses tier-based daily caps, and outputs the final detention amount.
• Determines the approval path:
  • $150 or less: auto-approval.
  • Above $150: calls OpenAI to draft a settlement offer email body (optionally using an HTTP carrier-performance lookup tool for tier/on-time context).
• Sends the offer for broker manager review in Gmail and waits for an Approve/Reject decision.
• Commits approved charges to your TMS using the TMS accessorial-charge API, then emails the carrier a confirmation via Gmail.
• Handles rejection: appends a rejection record and denial message via Google Sheets and Gmail.
• Audits every outcome: logs approved/rejected results to Google Sheets for reporting.

Use cases

• Streamline detention/accessorial claim processing from intake to TMS posting—without manual calculations.
• Standardize settlement language for higher-value claims using OpenAI-assisted drafting.
• Route approvals to a broker manager with a clear Gmail-based approve/reject step and auditable logs.

Technical details

• n8n nodes/logic: if, set, code, gmail, merge, sticky note
• Integrations: OpenAI, Gmail, Google Sheets, plus an HTTP TMS accessorial-charge API (and optional carrier-performance lookup API)