For Agents
Compare carrier rates, generate shipping labels, build manifests, and cancel labels across UPS, FedEx, USPS, DHL, and regional couriers through one unified API.
Get started with AfterShip Shipping API in minutes using your preferred integration method.
# Add to your MCP client config (Claude Desktop, Cursor, Windsurf)
{
"jentic": {
"url": "https://api.jentic.com/mcp",
"auth": "oauth"
}
}
# Then ask your agent:
"compare shipping rates and generate a label"
# → Jentic returns the GET /events tool with parameter schema, agent executes.What an agent can do with AfterShip Shipping API API.
Compare shipping rates across multiple couriers for a single shipment
Generate a shipping label by selecting a quoted rate from a carrier
Cancel a generated label before the shipment is picked up
Build manifests so couriers can pick up the day's shipments
GET STARTED
Use for: I need to compare shipping rates across UPS, FedEx, and USPS for a parcel, Generate a shipping label for a 5kg package from New York to London, Cancel a previously generated label that was created in error, List all couriers configured for our AfterShip workspace
Not supported: Does not handle post-shipment tracking events, returns portals, or warehouse inventory — use for outbound rates, labels, manifests, and cancellations only (use AfterShip Tracking for delivery events).
Jentic publishes the only available OpenAPI specification for AfterShip Shipping API, keeping it validated and agent-ready.
Jentic publishes the only available OpenAPI specification for AfterShip Shipping API, keeping it validated and agent-ready. AfterShip Shipping (formerly Postmen) consolidates dozens of carrier APIs — UPS, FedEx, USPS, DHL, and many regional couriers — behind a single multi-carrier interface. The API covers the full outbound shipping lifecycle: comparing rates across couriers, generating labels, building manifests, listing courier accounts, and cancelling labels before pickup.
List configured courier accounts attached to the AfterShip workspace
Validate addresses against couriers before quoting rates
Manage carrier-specific options like signature required and Saturday delivery
Patterns agents use AfterShip Shipping API API for, with concrete tasks.
★ Multi-Carrier Rate Shopping
E-commerce platforms call POST /rates with origin, destination, and parcel details to receive a list of carrier rates ranked by price and transit time. The shopper or merchant picks the best rate and the platform generates a label by referencing the chosen rateId. This avoids the per-carrier integration cost — one API call returns UPS, FedEx, USPS, and DHL options.
Call POST /rates with a 2kg parcel from 10001 New York to 90001 Los Angeles and return the top three carrier options sorted by total cost
Automated Label Generation
Order management systems generate shipping labels at fulfilment time by calling POST /labels with the chosen rateId from the rate-shop step. The response includes a printable PDF or PNG label plus the tracking number, which is written back to the order record. Replaces per-carrier label SDK integrations and works across UPS, FedEx, USPS, DHL, and regional couriers.
After picking the cheapest UPS rate from POST /rates, call POST /labels and save the returned label PDF and tracking number to the order
End-of-Day Manifest Creation
Warehouses call POST /manifests at the end of the picking shift so each courier has a single document listing all packages to collect. The manifest groups labels generated that day into a SCAN form (UPS), end-of-day manifest (FedEx), or equivalent. Cancellations before manifest creation use POST /cancel-labels to keep the document clean.
Build today's manifest for the UPS courier account, then cancel any labels in error status from the same day
AI Agent Fulfilment Operations
Through Jentic, an agent can run shipping operations end-to-end — quote, label, manifest — without holding the AfterShip API key. The agent searches for the operation, loads the schema, and Jentic injects the as-api-key header at execution time, returning a structured response.
Search Jentic for 'generate shipping label aftership', load the POST /labels schema, and execute it for an order with the chosen UPS rateId
28 endpoints — jentic publishes the only available openapi specification for aftership shipping api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
/rates
Compare rates across multiple couriers
/rates/{rateId}
Retrieve a specific rate quote
/labels
Generate a shipping label from a quoted rate
/labels/{labelId}
Retrieve a generated label
/manifests
Create a manifest for a courier
/couriers
List configured courier accounts
/cancel-labels
Cancel one or more generated labels
/rates
Compare rates across multiple couriers
/rates/{rateId}
Retrieve a specific rate quote
/labels
Generate a shipping label from a quoted rate
/labels/{labelId}
Retrieve a generated label
/manifests
Create a manifest for a courier
Three things that make agents converge on Jentic-routed access.
Credential isolation
AfterShip API keys are stored encrypted in the Jentic vault and injected into the as-api-key header per call. Agents never hold the raw key, which matters because the same key signs label-generation requests that incur real shipping costs.
Intent-based discovery
Agents search Jentic by intent (e.g., 'compare shipping rates') and Jentic returns the matching AfterShip Shipping operation with its schema, so the agent calls /rates or /labels without reading the docs.
Time to first call
Direct AfterShip Shipping integration: 2-4 days for auth, rate-shop, label, and manifest flows. Through Jentic: under 1 hour — search, load, execute.
Alternatives and complements available in the Jentic catalogue.
Shippo API
SMB-friendly multi-carrier shipping API with similar rate-shop and label flows.
Pick Shippo for smaller merchants who want a simple, cheap shipping API. AfterShip Shipping suits higher-volume and international shippers.
ShipStation API
Order-oriented multi-carrier shipping API focused on warehouse fulfilment workflows.
Choose ShipStation when the workflow centres on order picking and store integrations. Choose AfterShip Shipping when carrier coverage and label flexibility matter more.
Easyship API
Multi-carrier shipping platform with strong cross-border tax and duties support.
Pick Easyship when cross-border duties and taxes are the dominant pain point.
Shopify Admin API
Storefront platform that often hosts the orders being shipped.
Pair with Shopify so the agent can fulfil Shopify orders by quoting rates and printing labels via AfterShip Shipping.
Specific to using AfterShip Shipping API API through Jentic.
Why is there no official OpenAPI spec for AfterShip Shipping API?
AfterShip does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call AfterShip Shipping API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.
What authentication does the AfterShip Shipping API use?
AfterShip Shipping uses an API key sent in the as-api-key request header. Through Jentic, that header is populated at execution time from the encrypted vault, so the agent never holds the raw key.
Can I generate a UPS or FedEx label with the AfterShip Shipping API?
Yes. POST /rates returns rate options across all configured couriers (UPS, FedEx, USPS, DHL, and regional partners), then POST /labels generates the label for the chosen rateId. AfterShip handles the per-carrier API calls under the hood.
What are the rate limits for the AfterShip Shipping API?
The spec does not list explicit rate limits, but AfterShip enforces per-plan limits on calls per minute. Most fulfilment integrations stay well under the limit; back off on HTTP 429 if you hit it during peak periods like Black Friday.
How do I generate a label through Jentic?
Search Jentic for 'generate aftership shipping label', load the POST /labels schema, and execute with the chosen rateId from a prior /rates call. Jentic returns the label PDF URL and tracking number to the agent.
Is the AfterShip Shipping API the same as AfterShip Tracking?
No. This API (formerly Postmen) handles outbound shipping — rates, labels, manifests. AfterShip Tracking is a separate product covering post-shipment delivery events. Use this API to get a parcel out the door, not to track it after pickup.
/couriers
List configured courier accounts
/cancel-labels
Cancel one or more generated labels