> ## Documentation Index > Fetch the complete documentation index at: https://docs.upwell.com/llms.txt > Use this file to discover all available pages before exploring further. # Can I…? > The feasibility reference: what the Upwell API supports today, what has caveats, what it does not do, and what is real but undocumented — with evidence for every row. # Can I…? Feasibility before code. **✅ Supported** (documented and real) · **⚠️ Supported with caveats** (read the note) · **❌ Not supported** (today, as documented) · **❓ Undocumented** (the API surface exists in the OpenAPI spec but no guide covers it — confirm with Upwell before relying on it). **\[GAP]** marks questions the docs cannot answer yet. ## Accounts payable | Can I… | | Notes | | ------------------------------------------------------- | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ | | submit carrier invoices via API? | ✅ | [Submission guide](/api-guides/carrier-invoice-submission) | | attach documents and get them AI-classified? | ✅ | Presigned flow only — base64 uploads are filed, never classified ([Integration patterns](/integration-patterns)) | | know when an invoice is processed? | ✅ | Poll signals + webhooks ([status guide](/api-guides/carrier-invoice-status)) | | see every status the lifecycle can produce? | ⚠️ | The spec's enum has 16 values; 13 are defined in prose — `AWAITING_BILL`, `CANCELLED`, `REFUNDED` **\[GAP]** | | own approve/reject in my system? | ✅ | [Approval requests](/api-guides/carrier-invoice-approval) — PATCH `SUCCEEDED`/`FAILED` | | approve an invoice programmatically on the Upwell side? | ❓ | `POST /carrier_invoices/{id}/approve` (+`overrideExceptions`) exists in the spec; no guide covers it | | list only *pending* approval requests? | ⚠️ | Documented params are limit/offset; a `where` filter is pending transport verification — see [filtering](/developer-guide/what-happens-if#reading-data-back) | | read the catalog of exception types/tokens? | ❌ | No catalog exists; the `exceptions` string's token format is inconsistent across pages **\[GAP]** | | work exceptions (list/resolve) via API? | ❌ | No exceptions resource; lifecycle is UI-documented only ([Exceptions](/concepts/exceptions)) | | record carrier payments? | ✅ | Payment line items + bulk ([submission guide](/api-guides/carrier-invoice-submission)) | | read, correct, or delete carrier payments? | ❓ | GET/PUT/DELETE exist in the spec; guides document POST only | | use bill payments (settlement objects)? | ❓ | Full `bill-payments` endpoint family in spec; zero prose | | manage bill line items? | ❓ | Endpoints + nested create exist in spec; the bills guide never mentions line items | | pay lumpers/factors (non-carrier payables)? | ✅ | Vendors + `vendorId` on bills ([syncing guide](/api-guides/syncing-foundation-entities)) | | upload & parse POs and vendor invoices? | ✅ | [PO & vendor invoices guide](/api-guides/purchase-orders-and-vendor-invoices) | | get an event when a PO/vendor invoice finishes parsing? | ❌ | No trigger exists in the [catalog](/api-guides/webhook-events); poll `GET /documents/{id}` | | retract/delete a submitted carrier invoice? | ❓ | `DELETE /carrier_invoices/{id}` in spec; no guide, no semantics documented | | configure auto-approval via API? | ❌ | Dashboard settings only ([Approvals](/concepts/approvals)); cadence unpublished **\[GAP]** | ## Accounts receivable | Can I… | | Notes | | ----------------------------------------------------- | -- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | create invoices with line items in one call? | ✅ | Nested `invoiceLineItems` ([guide](/api-guides/customer-invoices)) | | link an invoice to shipments? | ✅ | Nested `invoiceShipments` on create (now in the spec) or `POST /invoice_shipments` ([guide](/api-guides/customer-invoices)) | | make Upwell deliver the invoice (email/EDI/portal)? | ⚠️ | The product does; the API action that triggers delivery is undocumented — confirm per tenant **\[GAP]** | | record customer payments/remittances? | ✅ | [Customer payments](/api-guides/customer-payments) | | have payments auto-update invoice balance/status? | ❌ | Your integration updates the invoice ([guide Tip](/api-guides/customer-invoices)) | | update or unapply a payment line item? | ❓ | PUT/DELETE exist in spec; guide names GET/POST only | | get events for payments recorded inside Upwell? | ⚠️ | Triggers exist ([catalog](/api-guides/webhook-events)); payload shapes undocumented **\[GAP]** | | drive reminders/dunning via API? | ❌ | No reminders API exists — email reminders are configured in the dashboard ([Payment Reminders](/accounts-receivable/reminders)) | | manage payment plans / disputes / bank feeds via API? | ❌ | No API surface; banking-integration ingestion is Upwell-operated ([Remittances](/accounts-receivable/remittances)) | | integrate the customer payment portal? | ❓ | Payments land as ordinary `customer_payments` ([Online Payments](/accounts-receivable/online-payments)); `portalSlug` exists on invoice reads; no portal API is documented | | track whether a customer opened an invoice? | ❓ | `VIEWED` exists in the status enum; no page explains who sets it or when | | send statements / list bills? | ⚠️ | Statements are a product feature ([Receivables](/accounts-receivable/receivables)); no API surface documented | ## Foundation data & sync | Can I… | | Notes | | ------------------------------------------------------- | -- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- | | push customers, carriers, shipments, companies, bills? | ✅ | [Syncing foundation entities](/api-guides/syncing-foundation-entities) | | bulk-load for the initial sync? | ⚠️ | bulk-customers/carriers/bills exist; **no bulk-shipments**; batch failure semantics differ per endpoint | | upsert everything by my own IDs? | ⚠️ | Works everywhere except **addresses** (no external key — store `addr_` ids); POST duplicate semantics differ per resource | | get called back when foundation data changes in Upwell? | ❌ | By design — no foundation-entity triggers ([catalog](/api-guides/webhook-events)) | | search/filter server-side? | ⚠️ | `POST /search` on 12 resources; addresses/companies have none; GET `?where=` pending verification ([details](/developer-guide/what-happens-if#reading-data-back)) | | page safely through big collections? | ✅ | limit/offset; **default limit is 10** — always pass it explicitly ([API conventions](/api-reference/introduction)) | | model multi-stop routes? | ⚠️ | `stops` nested + standalone CRUD; populate free-text `stopType` (it's what's read), draw values from the `type` enum | | model bill-to hierarchies? | ✅ | `billToCustomerId` ([syncing guide](/api-guides/syncing-foundation-entities)) | | merge duplicate customers? | ❌ | Internal operation; treat `mergedIntoCustomerId` as read-only ([syncing guide](/api-guides/syncing-foundation-entities)) | ## Events & platform | Can I… | | Notes | | -------------------------------------------------------- | -- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | subscribe to carrier-invoice lifecycle events? | ⚠️ | Per-status triggers only for `APPROVED`/`EXCEPTION`; no `PAID`/`UNDER_REVIEW` triggers ([status guide](/api-guides/carrier-invoice-status)) | | subscribe to carrier-document / invoice-APPROVED events? | ⚠️ | Exist but not self-service — marked † in the [catalog](/api-guides/webhook-events); contact support | | manage webhook subscriptions via API? | ❌ | Dashboard only ([webhooks guide](/api-guides/webhooks)) | | verify deliveries cryptographically (HMAC)? | ❌ | Static header/Basic auth only — no signing or replay protection ([webhooks guide](/api-guides/webhooks)) | | inspect or replay past deliveries? | ❌ | No surface exists; recover by polling ([webhooks guide](/api-guides/webhooks), Reliability) | | trust that 4xx responses will be retried? | ❌ | **They are not — and they're recorded as delivered.** Alert on your own 4xx rate ([webhooks guide](/api-guides/webhooks)) | | test against a sandbox? | ⚠️ | `staging.api.upwell.com` exists; access is provisioned by Upwell, and keys are environment-specific ([Environments](/authentication#environments)) | | plan around published rate limits? | ✅ | None exist today — no `429`/`X-RateLimit-*` ([Error handling](/api-reference/error-codes)) | | serve many Upwell tenants with one credential? | ❌ | One API key = one organization; no partner credential ([Key scope](/authentication#key-scope)) | | rotate/revoke an API key? | ✅ | Create → switch → revoke, in the dashboard; no key-management API ([Authentication](/authentication)) | | generate a client from the OpenAPI spec? | ✅ | The spec declares auth, required fields, real enums, nested inserts, and 400/401 responses; one caveat — `where`/`orderBy` filters pending verification ([details](/developer-guide/what-happens-if#errors-limits-and-the-reference)) | | follow API changes over time? | ⚠️ | The [changelog](/changelog) is the channel; entries are docs-only so far, and no deprecation policy is published **\[GAP]** | Rows marked ❓ are opportunities as much as risks: the surface exists and is tenant-scoped like everything else, but it is undocumented and therefore unwarranted — get written confirmation from Upwell before building on one. Full evidence trail for every row lives in the review bundle (`doc/HISTORY/2026-08-external-docs-dev-review/feasibility-matrix.md` in the repo).