> ## Documentation Index > Fetch the complete documentation index at: https://docs.ledgersyncappv2.com/llms.txt > Use this file to discover all available pages before exploring further. # Reauthorize a connection, or add accounts opened later > Mint a hosted page the end-user opens to re-consent at the institution, normally keeping the SAME `con_` / `acc_` / `txn_` ids. Two distinct reasons to call it: 1. **Repair.** The connection reports `status = requires_action` and the aggregator needs the end-user to re-enter credentials or re-consent. 2. **Add an account opened after link time.** The hosted page re-opens the institution's account-selection step, so an account the end-user opened (or chose not to share) after the original link can be ticked and starts syncing. This is the supported way to pick up such an account on a `FINICITY` connection, where `POST /connections/{connection_id}/refresh` only updates accounts we already hold. **This endpoint is not gated on status.** It is equally callable on an `active` connection, which is what makes reason 2 work. ### Why not just create a new connection? `POST /clients/{client_id}/connections` starts a **fresh** connection. When the aggregator issues a new underlying login for the same bank, that mints new `con_` / `acc_` / `txn_` ids for the same underlying account, so a later delta pull returns transactions you already have under **new** ids (your upsert would duplicate them). Reauthorize repairs the existing connection instead, so the ids stay stable and a delta re-sync over the overlap window dedupes cleanly on `txn_…`. That holds for every response whose `source` matches the source segment of the `connection_id` you sent, which is the normal case; see "Ids are not always stable" below for the one response shape where it does not. ### What you get back A hosted `reauth_url`, a LedgerSync-hosted page the end-user opens to complete the source-specific flow (Finicity Connect Fix, MX member reconnect, FDE credential recapture) against the existing connection. Redirect the user to it, then wait for the `connection.active` / `connection.failed` webhook for the outcome. The response also carries `source`: the provider the URL leads to. See "Ids are not always stable" below. ### The URL is a reusable bearer credential The link is **not** single-use. It stays valid until `action.expires_at` (currently about six days out) and anyone holding it can open the end-user's bank-linking session. Deliver it over a channel you would use for a password reset, do not log it, and do not embed it in a page that a third party can scrape. ### Ids are not always stable For a bank LedgerSync now serves exclusively through a different provider, the URL we hand back is an add-bank link for that provider rather than a repair link for the connection you named. Today that is Finicity connections at such banks being redirected to MX, and American Express is on that list in production. The list is configuration and can change without an API version bump, so branch on the response rather than on a bank you hard-coded. When the redirect happens, the end-user's session creates a **new** connection with a new `con_` id and new `acc_` / `txn_` ids, and the connection you passed is left as it was. Detect it from the response: `source` differs from the source segment of the `connection_id` you sent. On that branch the `connection.active` webhook that follows carries the **new** connection's id, not the one you passed, so key off the Client rather than the connection: wait for `connection.active`, then re-list `GET /v3/connections` and `GET /v3/accounts` for that Client and re-map, rather than expecting the old ids to come back. ### Call it because a person asked, not on a timer Each completed session can share accounts you were not syncing before, and newly shared accounts pull their statement history, which is billable. Trigger this from an explicit user action. Do not schedule it, do not retry it in a loop, and do not mint a second link while the first is still valid. Available for `FINICITY`, `MX`, and `FDE`. Uploaded-statement (`PDF`) data is read-only and has no connection to reauthorize (`400`). On `MX` and `FDE` you do not need this endpoint to pick up a newly opened account: a plain refresh discovers it. See `POST /connections/{connection_id}/refresh`. Ownership is enforced server-side: a `connection_id` that doesn't belong to the authenticated customer returns `404`. ### Empty-body POST This endpoint takes no request body. Send an explicit `Content-Length: 0` header so the upstream HTTPS load balancer doesn't reject the request with `411 Length Required`. ## OpenAPI ````yaml /openapi.yaml post /connections/{connection_id}/reauthorize openapi: 3.1.0 info: title: LedgerSync API version: '2026-05-22' summary: A modern REST API for connecting bank accounts and pulling financial data description: > > **First time here?** The [**Getting started** guide](https://portal.ledgersyncappv2.com/dashboard/getting-started) walks the full integration end-to-end (about 15 minutes). This page is the endpoint reference for after you've read it. Welcome. This is LedgerSync's API for connecting your users' bank accounts and pulling their transactions, statements, and account details. Everything is JSON over HTTPS. Errors are easy to read. Webhooks fire as state changes. Sandbox is one key away. ## Connection lifecycle and the two `connection.id` formats A Connection's `id` changes shape once the user finishes linking their bank — there are two distinct identifiers, and you must only use the canonical one to read accounts, transactions, or statements. 1. **Placeholder id (pending state).** `POST /v3/clients/{id}/connections` returns `202 Accepted`. The initiate operation first surfaces a `connection_with_action` result whose embedded `connection.id` is a UUID-prefixed placeholder of the form `con_` (e.g. `con_01HXYZ8A6N7K2W9PQ4T5Z3V6E0`), paired with a `widget_url`. The placeholder is **not** a valid id for any other endpoint — calling `GET /v3/connections/{placeholder_uuid}` returns `400 Bad Request` with `missing source separator`. Treat it as opaque routing state for the widget step only. 2. **Canonical id (active state).** Once the user finishes the widget and the source pushes its first callback, the connection moves to `status=active` and the `connection.active` webhook fires. From that point on every surface — `GET /v3/clients/{id}/connections`, `GET /v3/connections/{id}`, the webhook payload, and the `connection.initiate` operation when re-polled — reports the canonical id `con__` (for example `con_FINICITY_41294`, `con_MX_1224`). **This** is the id every other endpoint accepts (`/accounts`, `/transactions`, `/statements`, refresh, delete). The correct integration pattern is therefore: - Initiate the connection, capture `operation_id`. - Poll `GET /v3/operations/{operation_id}` (or wait for the `connection.active` webhook) until `status=succeeded`. - Read `result.connection.id` **from the succeeded operation** — that is the canonical id. Store it; do not store the placeholder. Do not try to `GET /v3/connections/{placeholder_uuid}` during the pending window. Listing endpoints (`GET /v3/clients/{id}/connections`, `GET /v3/connections/{id}`) only ever return canonical ids, because they only surface connections that have reached `active`. ## Quick start Mint a sandbox key in the developer portal, then create your first **Client** (your end-user — the person whose bank we'll be reading): ```bash curl \ https://api-sandbox.ledgersyncappv2.com/v3/clients \ -H "Authorization: Bearer sk_test_..." \ -H "Content-Type: application/json" \ -d '{"email":"alice@example.com","name":"Alice"}' ``` You'll get back a `Client` object with an `id`. From there the full flow is: 1. **Register a webhook** at `POST /v3/webhooks/subscriptions` so you can be notified when the connection progresses. 2. **Initiate a connection** at `POST /v3/clients/{id}/connections` with an `institution_id` from `GET /v3/institutions`. LedgerSync's router picks the underlying source. Every source hands back a `widget_url` in the `connection.requires_action` result — for FDE it points at a LedgerSync-hosted connect page where credentials are entered, never sent to the API. 3. **Open the widget URL** in your user's browser. They pick their bank, log in, and choose accounts to share. 4. **Receive `connection.active`** on your webhook URL. List accounts and transactions. **Don't want to build your own bank picker?** Skip steps 2–3: call `POST /v3/clients/{id}/connect-session` to get a LedgerSync-hosted link, and email it to your member. They open it, search for their own bank, pick it, and connect it — all on a page we host, with no `institution_id` needed up front. You still receive `connection.active` on your webhook exactly as above. Revoke a link at any time with `DELETE /v3/clients/{id}/connect-session/{sid}`. (This is the v3 replacement for the old `account/add/lite` widget.) Want a step-by-step walkthrough with curl per step plus a sandbox shortcut that skips the widget? Read the [Getting started guide](https://portal.ledgersyncappv2.com/dashboard/getting-started). ## Authentication Pass your secret key in the `Authorization` header as a Bearer token: `Authorization: Bearer sk_test_...` (sandbox) or `Bearer sk_live_...` (production). Treat secret keys like passwords — never embed them in mobile apps or front-end code. ## Conventions **Sync vs async.** Most endpoints respond synchronously — you get the resource back right away. A handful of flows are genuinely async (initiating a bank connection, extracting a statement, generating a verification report); those return `202 Accepted` with an `operation_id` you can poll, and the matching webhook fires when the work finishes. **Errors.** Every error is `{ "error": { "code", "message", "doc_url", "type" } }`. Branch on `code`. Click `doc_url` for the troubleshooting page. Every response carries an `X-LS-Trace-Id` header — paste it in support tickets and we can jump straight to your request. **Webhooks.** Every delivery carries `X-LS-Webhook-Signature`, computed over the **raw request body** with HMAC-SHA256. Verify it before trusting the payload. Full event catalog + signature example on the [Webhooks tab](#webhooks). ## Need help? Email [support@ledgersync.com](mailto:support@ledgersync.com) or open a thread in the developer portal. Quote the `X-LS-Trace-Id` from your response — it makes everything faster. contact: name: LedgerSync Developer Support email: support@ledgersync.com url: https://portal.ledgersyncappv2.com license: name: Proprietary url: https://ledgersync.com/terms servers: - url: https://api-sandbox.ledgersyncappv2.com/v3 description: >- Sandbox — use `sk_test_...` keys from the developer portal. Routes to the real Finicity and MX sandbox banks (FinBank, mxbank) via the same connector code paths as production. - url: https://api.ledgersyncappv2.com/v3 description: >- Production — use `sk_live_...` keys. Hits real banks via Finicity, MX, or FDE depending on the connection. security: - bearer: [] tags: - name: Clients description: | A **Client** is the end-user whose bank accounts you're managing — usually a real person or business. You create one Client per user before linking any accounts. Pass your own `external_id` to join Clients back to records in your system. - name: Connections description: | A **Connection** links a Client to a bank or financial-data source (Finicity, MX, or FDE). One Client can have many Connections — one per bank they've linked. You initiate a Connection, the user finishes it (widget or MFA), and a `connection.active` webhook tells you when it's ready. - name: Accounts description: | Once a Connection goes active, the bank's accounts (checking, savings, credit, loans) show up here. Use these endpoints to list, inspect, and refresh them. - name: Transactions description: | Posted transactions and pending charges for an account. New transactions are surfaced by a future push-delivery event for transactions after each refresh; you can also list/page them directly. - name: Statements description: | Period statements (usually monthly PDFs) the bank publishes. For FDE-sourced statements, extracted line items are attached after OCR completes. - name: Checks description: | Images of paper checks, captured alongside FDE statement extraction. FDE-only: Finicity and MX report `check_images` as `unsupported`. Fronts only — LedgerSync does not capture the back of a check, so there is no `side` field. - name: Operations description: | The handful of LedgerSync calls that genuinely run asynchronously return an `operation_id`. Poll it here, or just listen for the matching webhook — your call. - name: Webhooks description: | Manage where LedgerSync delivers event notifications. Each subscription has its own HMAC signing secret. Rotate it whenever you want — the old secret stays valid for 24 hours so deploys don't break verification. - name: ApiKeys description: | Create, list, and revoke API keys. Keys are scoped to one environment (sandbox or live). The plaintext secret is returned exactly once at creation — store it somewhere safe. - name: Institutions description: | The unified v3 institution catalog. Search by name; pick a row; pass its `id` to `POST /clients/{client_id}/connections`. LedgerSync's router decides which underlying source (Finicity, MX) to use — integrators don't pick a source. - name: Settings description: | Account-level settings the integrator manages once per environment. Currently exposes the redirect-URL allowlist consulted at `/connections/initiate`. Same scope as Stripe Connect / Plaid Link / OAuth — register your app's redirect URIs once, not per end-user. - name: Sandbox description: | Sandbox-only helpers. Use `GET /sandbox/institutions` to list the sandbox-eligible test banks you can target when creating a sandbox connection (Finicity FinBank, MX `mxbank`, FDE test extractors). Lifecycle transitions and webhooks come from the same real connector paths as live traffic — no synthetic lifecycle driver, no replay fixtures. Drive the widget with the public test bank credentials documented in the developer portal. - name: Metrics description: | Read-only aggregations powering the developer portal's "Metrics" page. Every endpoint is scoped to the authenticated principal's customer and environment — `sandbox` and `live` data never mix across the wire. Default window when `from`/`to` are omitted is the last 30 days (max 366). - name: Health description: A simple liveness probe. No auth required. - name: PortalGating description: | Developer-portal access-request endpoints (sandbox + live gating). These are HMAC-signed calls from the LedgerSync portal to v3 and not part of the integrator-facing API surface. Documented here so the single spec stays authoritative. paths: /connections/{connection_id}/reauthorize: parameters: - in: path name: connection_id required: true description: | Canonical Connection id (`con__`) of the connection to repair, or of the active connection whose account selection you want the end-user to revisit. The placeholder UUID from initiate and any `con_PDF_*` id are rejected with `400`. schema: type: string example: con_FINICITY_41294 post: tags: - Connections summary: Reauthorize a connection, or add accounts opened later description: | Mint a hosted page the end-user opens to re-consent at the institution, normally keeping the SAME `con_` / `acc_` / `txn_` ids. Two distinct reasons to call it: 1. **Repair.** The connection reports `status = requires_action` and the aggregator needs the end-user to re-enter credentials or re-consent. 2. **Add an account opened after link time.** The hosted page re-opens the institution's account-selection step, so an account the end-user opened (or chose not to share) after the original link can be ticked and starts syncing. This is the supported way to pick up such an account on a `FINICITY` connection, where `POST /connections/{connection_id}/refresh` only updates accounts we already hold. **This endpoint is not gated on status.** It is equally callable on an `active` connection, which is what makes reason 2 work. ### Why not just create a new connection? `POST /clients/{client_id}/connections` starts a **fresh** connection. When the aggregator issues a new underlying login for the same bank, that mints new `con_` / `acc_` / `txn_` ids for the same underlying account, so a later delta pull returns transactions you already have under **new** ids (your upsert would duplicate them). Reauthorize repairs the existing connection instead, so the ids stay stable and a delta re-sync over the overlap window dedupes cleanly on `txn_…`. That holds for every response whose `source` matches the source segment of the `connection_id` you sent, which is the normal case; see "Ids are not always stable" below for the one response shape where it does not. ### What you get back A hosted `reauth_url`, a LedgerSync-hosted page the end-user opens to complete the source-specific flow (Finicity Connect Fix, MX member reconnect, FDE credential recapture) against the existing connection. Redirect the user to it, then wait for the `connection.active` / `connection.failed` webhook for the outcome. The response also carries `source`: the provider the URL leads to. See "Ids are not always stable" below. ### The URL is a reusable bearer credential The link is **not** single-use. It stays valid until `action.expires_at` (currently about six days out) and anyone holding it can open the end-user's bank-linking session. Deliver it over a channel you would use for a password reset, do not log it, and do not embed it in a page that a third party can scrape. ### Ids are not always stable For a bank LedgerSync now serves exclusively through a different provider, the URL we hand back is an add-bank link for that provider rather than a repair link for the connection you named. Today that is Finicity connections at such banks being redirected to MX, and American Express is on that list in production. The list is configuration and can change without an API version bump, so branch on the response rather than on a bank you hard-coded. When the redirect happens, the end-user's session creates a **new** connection with a new `con_` id and new `acc_` / `txn_` ids, and the connection you passed is left as it was. Detect it from the response: `source` differs from the source segment of the `connection_id` you sent. On that branch the `connection.active` webhook that follows carries the **new** connection's id, not the one you passed, so key off the Client rather than the connection: wait for `connection.active`, then re-list `GET /v3/connections` and `GET /v3/accounts` for that Client and re-map, rather than expecting the old ids to come back. ### Call it because a person asked, not on a timer Each completed session can share accounts you were not syncing before, and newly shared accounts pull their statement history, which is billable. Trigger this from an explicit user action. Do not schedule it, do not retry it in a loop, and do not mint a second link while the first is still valid. Available for `FINICITY`, `MX`, and `FDE`. Uploaded-statement (`PDF`) data is read-only and has no connection to reauthorize (`400`). On `MX` and `FDE` you do not need this endpoint to pick up a newly opened account: a plain refresh discovers it. See `POST /connections/{connection_id}/refresh`. Ownership is enforced server-side: a `connection_id` that doesn't belong to the authenticated customer returns `404`. ### Empty-body POST This endpoint takes no request body. Send an explicit `Content-Length: 0` header so the upstream HTTPS load balancer doesn't reject the request with `411 Length Required`. operationId: reauthorizeConnection requestBody: required: false description: | No body. Send `Content-Length: 0` so the upstream load balancer doesn't reject the request with 411. content: application/json: schema: type: object nullable: true responses: '200': description: | A hosted reauthorization URL, plus the `source` it leads to. Same source as the `connection_id` means the existing connection is repaired and its ids stay stable; a different one means the URL mints a new connection. headers: X-LS-Trace-Id: $ref: '#/components/headers/X-LS-Trace-Id' content: application/json: schema: $ref: '#/components/schemas/ConnectionReauthorization' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '404': $ref: '#/components/responses/NotFound' '411': description: | Returned by the upstream HTTPS load balancer when a POST arrives without a `Content-Length` header. Retry with `Content-Length: 0` set explicitly. '502': description: | The aggregator or the backend was unreachable while minting the reauthorization URL, so nothing was issued. Body carries the canonical `ErrorEnvelope` (typically `error.code = "upstream_unavailable"`); retry shortly. headers: X-LS-Trace-Id: $ref: '#/components/headers/X-LS-Trace-Id' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' components: headers: X-LS-Trace-Id: description: Distributed-trace ID for this request. Quote in support tickets. schema: type: string example: 4bf92f3577b34da6a3ce929d0e0e4736 schemas: ConnectionReauthorization: type: object description: | Result of `POST /v3/connections/{connection_id}/reauthorize`: the connection id (echoed for correlation), the source the hosted URL actually leads to, and a `reauthorize` action carrying that URL. required: - connection_id - source - action properties: connection_id: type: string example: con_FINICITY_41294 source: allOf: - $ref: '#/components/schemas/Source' description: | The source the hosted URL leads to. Usually the same source as the `connection_id` you passed, meaning the existing connection is repaired in place and its ids stay stable. When it differs, the URL hands the end-user to a different provider (today: a Finicity connection at a bank we now serve exclusively through MX). Completing it creates a **new** connection with a new `con_` id and new `acc_` / `txn_` ids under the same Client; the old connection is not repaired. Compare this against the source segment of the `connection_id` you sent, and if it differs, re-list `GET /v3/connections` and `GET /v3/accounts` for the Client after the `connection.active` webhook rather than expecting the old ids to come back. example: FINICITY action: $ref: '#/components/schemas/ConnectionActionReauthorize' ErrorEnvelope: type: object description: | Error envelope returned as the top-level body of every non-2xx HTTP response. The actual error payload lives in the `error` field — branch on `error.code`. required: - error properties: error: $ref: '#/components/schemas/ErrorInfo' Source: type: string description: | Financial-data source backing an account. Aggregator sources (`FINICITY`, `MX`) and `FDE` back a Connection; `PDF` does not. Values: - `FINICITY` — Finicity aggregation - `MX` — MX aggregation - `FDE` — Financial Document Extraction (LedgerSync proprietary) - `PDF` — Uploaded bank statements. Read-only: exposed on `/accounts` and `/transactions` (statements are not served for PDF), and never as a Connection (PDF accounts have `connection_id: null`). enum: - FINICITY - MX - FDE - PDF x-enum-descriptions: - Finicity aggregation - MX aggregation - Financial Document Extraction (LedgerSync proprietary) - Uploaded bank statements (read-only; not a connection source) ConnectionActionReauthorize: type: object required: - kind - reauth_url - expires_at properties: kind: type: string enum: - reauthorize reauth_url: type: string format: uri expires_at: type: string format: date-time ErrorInfo: type: object description: | The inner error payload. Used as the top-level body of an HTTP error response (wrapped in `ErrorEnvelope`) and as the embedded `error` field on resources that record a failure (like `Operation.error`). required: - code - message - type properties: code: type: string description: | Stable machine-readable identifier. Branch on this in your code, not on `message`. example: unknown_api_key message: type: string description: Plain-English explanation safe to log. example: The API key you presented doesn't match any active key. doc_url: type: string format: uri description: | Link to the docs page for this specific error code. Shareable with teammates in support tickets. example: https://portal.ledgersyncappv2.com/errors/unknown_api_key type: type: string description: | Stripe-style broad failure-mode category — useful for "treat all of these the same way" branches. Derived from the HTTP status. Orthogonal to `category`, which classifies by origin. enum: - auth_error - invalid_request - rate_limit_error - idempotency_error - not_found - api_error example: auth_error category: type: string description: | Plaid-style coarse classification by origin. Branch on this for routing logic — retry the request, surface to the end user in the widget, or page on-call. Orthogonal to `type` (which is HTTP-status-derived). enum: - AUTH_ERROR - INSTITUTION_ERROR - CAPABILITY_UNAVAILABLE - CONNECTION_ERROR - RATE_LIMIT - INVALID_REQUEST - RESOURCE_NOT_FOUND - PLATFORM_ERROR example: AUTH_ERROR is_user_actionable: type: boolean description: | True when the end user can resolve this error (re-enter credentials, complete MFA, accept an updated agreement). False when the error requires institution-side or LS platform-side action. Useful for deciding whether to send the end user back to the widget or surface an "operational issue" banner. example: true source_diagnostic_code: type: string pattern: ^(FIN|MX|FDE)-[A-Z0-9_]+$ description: | Opaque upstream-source diagnostic identifier (e.g. `FIN-103`, `MX-DENIED`). Present only on errors that originated at an aggregator/extractor. Use for support triage — do NOT branch on this value; the unified `code` and `category` are the integrator-facing vocabulary. example: FIN-103 param: type: string description: | For validation failures (4xx), the request field that tripped the check. Dot-separated path for nested fields. example: client.email trace_id: type: string description: | Same as the `X-LS-Trace-Id` response header — paste in a support ticket to jump to the request. example: 4bf92f3577b34da6a3ce929d0e0e4736 errors: type: array description: | Per-field validation errors (only present on 400 when multiple fields failed at once). items: type: object required: - param - message properties: param: type: string example: client.email message: type: string example: must be a valid email address code: type: string example: invalid_email responses: BadRequest: description: | Something in the request body or query string didn't pass validation. The response carries `error.param` (or `error.errors[]` for multi-field failures) so you know which field to fix. headers: X-LS-Trace-Id: $ref: '#/components/headers/X-LS-Trace-Id' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' Unauthorized: description: | Either the `Authorization` header is missing or the bearer token doesn't match an active API key. Double-check the key and the environment — sandbox keys can't be used against the production base URL and vice versa. headers: X-LS-Trace-Id: $ref: '#/components/headers/X-LS-Trace-Id' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' NotFound: description: | We didn't find a resource matching the path parameters. Common causes: the id belongs to a different customer's key, the resource was deleted, or there's a typo in the id. headers: X-LS-Trace-Id: $ref: '#/components/headers/X-LS-Trace-Id' content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' securitySchemes: bearer: type: http scheme: bearer bearerFormat: LedgerSync API key description: | Pass your secret key in the `Authorization` header as a Bearer token: `Authorization: Bearer sk_test_...` (sandbox) or `Bearer sk_live_...` (production). Keys are created in the developer portal and the plaintext secret is shown exactly once at creation. Treat them like passwords — never embed them in mobile apps or front-end code. ````