Approve Carrier Detention Disputes: n8n, Gmail & Google Sheets

Approve Carrier Detention Disputes automatically—built with n8n, Gmail, and Google Sheets

Turn carrier detention and accessorial disputes into a streamlined approval workflow. This n8n automation collects claims from an n8n form, calculates billable detention with tier-based caps, drafts settlement offers with OpenAI, routes larger claims for manager approval in Gmail, and then posts approved charges to your TMS API while logging outcomes to Google Sheets.

What this workflow does

• Ingests detention/accessorial claims submitted via an n8n form (load details, timestamps, carrier tier, and contracted detention rate).
• Normalizes fields and calculates billable detention hours after 2 hours free time, then computes the detention amount.
• Applies daily caps by carrier tier to ensure detention charges are controlled according to your contract rules.
• Automatically approves smaller claims (below $150) and flags larger claims for review.
• Drafts settlement offer content for claims needing review using OpenAI, including an HTTP carrier-performance lookup tool.
• Requests approval in Gmail using send-and-wait behavior to a broker manager, then detects whether the manager approved or rejected.
• Commits approved charges to your TMS accessorial-charge API and emails the carrier a confirmation.
• Handles rejections by appending details to Google Sheets, emailing a denial to the carrier, and logging final decisions for auditing.

Use cases

• Broker teams processing frequent detention disputes and needing consistent, contract-based calculations.
• Operators who want manager approval only when claims exceed $150, reducing manual review.
• Teams that must maintain an audit trail of approvals/rejections in Google Sheets.

Technical details

• n8n stack/nodes: if, set, code, gmail, merge, and sticky note.
• Integrations: OpenAI for settlement drafting, Gmail for manager approval, Google Sheets for logging, and HTTP authentication for a Carrier Perf lookup.
• API actions: posts approved detention/accessorial charges to a TMS API and sends carrier emails with the final decision.