Retrieve all carrier accounts connected to your Shippo account via GET https://api.goshippo.com/carrier_accounts with your API token in the Authorization header (ShippoToken {token}).
The response returns a results array of carrier account objects, each with: object_id, carrier (e.g., ups, fedex, usps), account_id (the account number with the carrier), active (boolean), and test (boolean for sandbox accounts).
To retrieve a single carrier account, use GET /carrier_accounts/{object_id}.
To add a new carrier account, POST to /carrier_accounts with carrier, account_id, and parameters (carrier-specific credentials); check Shippo documentation for the parameters schema per carrier as it varies significantly.
To update credentials on an existing carrier account, PUT to /carrier_accounts/{object_id} with updated parameters.
Known gotchas
Carrier account credential schemas differ per carrier — the parameters object structure for UPS, FedEx, DHL, and USPS are all different; always consult the current Shippo carrier connection docs for the exact fields required.
Deactivating a carrier account (active: false) does not remove it; rates for that carrier will no longer be returned in rate shopping, but the account record persists and can be reactivated.
Shippo Reseller and multi-user accounts can have carrier accounts shared at the organization level; test accounts (test: true) are sandbox-only and will not generate real labels.
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp