> ## Documentation Index > Fetch the complete documentation index at: https://docs.lerian.studio/llms.txt > Use this file to discover all available pages before exploring further. # TED Lerian business rules > How TED Lerian applies the operating window, usage limits, fees, idempotency, regulatory deadlines and personal data rules. ## Operating window *** The effective window of a day combines three sources. `GET /v1/policy/window` returns which one decided (`source`). * **The official STR schedule**, published by Lerian SPB. Schedule changes the STR announces during the day apply without a restart. * **The institution's cut-off**, optional, always equal to or earlier than the official close. TED Lerian refuses a later time with `TED-0081`. * **The national holiday calendar**, kept per year. | Situation | Answer when you send a TED | | - | - | | Outside the schedule or after the cut-off | `422 TED-0020`, nothing held | | Weekend or holiday | `422 TED-0021`, nothing held | | The window could not be determined | `503 TED-0022`. TED Lerian refuses rather than guessing. | | Internal transfer | The STR window does not apply | ## Usage limits *** * Per source account: a maximum per transfer, a total per day and a total per month, by calendar day and month in Brasília time (`America/Sao_Paulo`). The ceilings follow the order transfer ≤ day ≤ month. A missing ceiling means no ceiling. * They count the total debited: the amount plus the fee. * An institution must configure its limits before the first TED. Without them, TED Lerian refuses each send with `503 TED-0080`. * Above a limit, TED Lerian refuses the TED before the hold with `422 TED-0030`. The answer names the limit. * A rejected or cancelled transfer frees them up again. * With `enabled=false`, the limits count nothing and refuse nothing. * Only the administrator changes them. Each change records who made it and when. ## Fees *** * Charging a fee is optional and off by default. While it is off, every fee is zero: on the quote, on sending and on receiving. * When it is on for an institution, Midaz calculates the fee from the configured fee package (`feePackageId`). * The quote shows the fee and the total with no financial effect. The quoted fee is the fee that a send of the same request would hold. * If the calculation is unavailable when you send, TED Lerian refuses the TED with `503 TED-0040`. The institution can choose to send with a zero fee in that case instead. * On an incoming TED, the fee shows in `feeAmount` and the credited amount in `creditedAmount`. If the calculation fails, the customer receives the full amount with a zero fee. * When another institution returns a TED, TED Lerian does not refund the sending fee by default. The institution can turn the refund on, and `returned.feeRefunded` shows what happened. ## Idempotency and duplicate requests *** * Every write needs the `X-Idempotency` header: 1 to 128 printable ASCII characters. Without it, the answer is `400 TED-0011`. * The same key with the same body returns the original response with `X-Idempotency-Replayed: true`. TED Lerian creates no new transfer. * `X-TTL` sets for how many seconds TED Lerian replays the response (default 300). Only the TTL of the first request counts. * A request with the same key and another body gets `422 TED-0012`. On `POST /v1/transfers`, the key stays bound to the transfer it created: a later request with the same key never creates a second transfer. * A request with the same key still in progress gets `409 TED-0013` with `Retry-After`. * Whatever the key, `POST /v1/transfers` refuses a materially identical request in the same anti-duplication window (5 minutes by default) with `409 TED-0014`. ## Regulatory deadlines *** | Deadline | Starts at | Ends at | Limit | | - | - | - | - | | Debit to submission | The debit hold | Submission to the STR | 30 min | | Settlement to credit | Interbank settlement at the STR | Credit to the recipient | 60 min | | Settlement to return | Interbank settlement at the STR | The return | 60 min | `GET /v1/operations/sla` shows p50, p95 and p99 for each deadline, the breaches of the day and the items at risk. ## Personal data *** * **API responses:** the name and the CPF or CNPJ of the sender and of the recipient come in full, for roles allowed to read them. * **Logs:** TED Lerian masks documents and names. * **Events for sent TEDs** (`transfer.*`) carry no counterparty data. * **Events for incoming TEDs** (`incoming_transfer.*`) carry the recipient, the institution's own customer, in full. The sender, a customer of another institution, is masked. * The free-text description of an incoming TED is published as the sending institution wrote it. ## Isolation between institutions *** Each record belongs to one institution. The institution always comes from the authenticated token, never from a field in the request. An identifier from another institution answers as not found (`404`), without revealing that it exists. ## Audit *** Each transfer has a timeline that is never edited. It records each status change with the date and time, the origin (`API`, `RAIL`, `STR`, `LEDGER`, `WORKER`, `OPERATOR`, `SYSTEM`), the official reason and, for operator actions, who acted. TED Lerian deletes no business record. This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.