# T+1 Settlement Prep > Take a trade file (recent trades that haven't settled yet) and walk every line against the business-day calendar plus the corporate-action calendar to flag trades with settlement risk. Catches holiday adjacency, weekend crossing, short-sale locate prompts, ex-dividend in the settlement window, mid-settlement splits, and half-day DTCC cutoffs. Exception-report mode. Runs on a free Stocks Basic key. - Skill: `rgourley/t-1-settlement-prep` (Agent Skill, multi-file: 10 files) - Install (CLI): `npx skillmds@latest add rgourley/t-1-settlement-prep` - Raw SKILL.md: https://api.skillmd.com/api/skills/rgourley/t-1-settlement-prep/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Docs & Writing - Author: rgourley (https://skillmd.com/u/rgourley) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/rgourley/t-1-settlement-prep --- # t+1-settlement-prep You hand over a trade file. The skill computes the T+1 settlement date for each row, walks the next 90 days of holidays + corporate actions, and emits an exception report listing only the trades that need operations attention before settlement. This is the operations-desk workflow that runs at end of trading day, between T and T+1. SEC moved US equities to T+1 in May 2024; the margin for error on settlement is now one business day, not three. A trade that crosses a long weekend or settles on a half-day session can break cash forecasting if nobody flagged it. ## When to invoke - Operations says "prep tonight's trades for settlement" or "run T+1 checks on this blotter" - Treasury asks "is cash going to be where it needs to be tomorrow" - A long weekend is coming up (3-day weekend, July 4, Thanksgiving) and ops wants visibility into which trades push into the following week - A corporate action calendar shows an ex-date inside the next two business days and you want to know which trades are exposed ## What you need - A trade CSV with columns: `ticker`, `side` (BUY/SELL/SHORT/COVER), `qty`, `trade_date` (YYYY-MM-DD) - `MASSIVE_API_KEY` exported. Stocks Basic is enough; the three endpoints this skill uses (`/v1/marketstatus/upcoming`, `/v3/reference/dividends`, `/v3/reference/splits`) are all on the free tier. ## What this skill flags Six categories. A trade can hit more than one. 1. **Holiday adjacency** (`holiday_adjacency`). T+1 lands on a US equity-market holiday; settlement pushes to the next business day. Operations needs to refund cash forecasts and notify treasury for the adjusted date. 2. **Weekend crossing** (`weekend_crossing`). T+1 lands on a Saturday or Sunday; settlement pushes to Monday. Treated as a separate flag from holiday_adjacency because cash desks model them differently (regular weekend vs irregular three-day weekend). 3. **Short-sale locate** (`short_sale_locate`). Side is SHORT. Reg SHO requires a locate before the trade can settle. The skill cannot read the prime broker's locate file, so this flag is a confirmation prompt rather than a hard break. 4. **Ex-dividend in window** (`ex_dividend_in_window`). The ticker has an ex-dividend date between trade_date and computed_settlement_date. Under T+1, ex-date and record-date are the same day, so the buyer's dividend entitlement turns on whether they purchased before the ex-date. The skill computes the dollar impact (qty * cash_amount) so operations can confirm the dividend allocation flag on the trade ticket. 5. **Corporate action overlap** (`corp_action_overlap`). A split or reverse split has an ex-date in the settlement window. DTCC handles the share-count adjustment automatically, but the post-action delivered quantity differs from the recorded trade quantity. Flagged as informational so settlement and position-reporting teams aren't surprised. Not a hard break. 6. **Half-day settlement** (`half_day_settlement`). Settlement date is a US equity early-close session (Thanksgiving Friday, Christmas Eve, July 3 when 7/4 falls on Saturday). DTCC's cutoff is earlier than the normal 15:00 ET deadline, typically 12:30 ET. Cash-management teams tighten their windows accordingly. ## What you get back Two output layers. **Layer 1: canonical JSON** matching [`output-schema.json`](./output-schema.json). Per flagged trade: ticker, side, qty, trade_date, computed settlement date, reason codes, impact text, suggested next action, plus typed substructures for `dividend`, `corp_action`, and `session_info` when those reasons fire. Per run: scan_params, settlement window dates, counts by reason. UI dashboards and downstream agents consume this. **Layer 2: rendered exception report**. Header with run metadata. One BREAK block per flagged trade. Summary block with counts by reason and the settlement-window date range. See [`references/rendering.md`](./references/rendering.md) for the full format. A short example: ``` T+1 settlement prep: 12 trades checked · 4 BREAKs flagged · run 2026-06-25 16:42 UTC BREAK 1: NVDA SHORT 200 · trade 2026-06-25 · settlement 2026-06-26 Reason: Short sale; locate confirmation required Impact: Trade may fail without locate on file before T+1 cutoff Suggest: Confirm locate ticket with prime broker before EOD ``` ## How it works 1. **Pull the holiday calendar** from `/v1/marketstatus/upcoming` once per run. Cache the response; the API returns one row per exchange per event (NYSE and NASDAQ each emit their own row for the same holiday). The skill de-dupes by `date` and treats NYSE as canonical. Half-day sessions appear as `status: "early-close"` with `open` and `close` UTC timestamps. Full closures are `status: "closed"` with no open/close. 2. **For each trade**, compute the naive settlement date as `trade_date + 1 calendar day`. Then walk forward: if the candidate is a weekend or a holiday, step one day and re-check. The first business day that survives is the computed settlement date. 3. **Set flag codes**: - `weekend_crossing` if naive settlement was Sat or Sun - `holiday_adjacency` if naive settlement was a closed market day (or computed settlement was pushed past one). These are tracked separately because cash desks model them differently. - `short_sale_locate` if `side == "SHORT"` 4. **Pull the dividend calendar** for each ticker via `/v3/reference/dividends?ticker={t}&ex_dividend_date.gte=...`. If any ex-date falls inside `[trade_date, computed_settlement_date]`, flag `ex_dividend_in_window` and populate the `dividend` substructure with `cash_amount`, `pay_date`, and dollar impact (qty * amount). 5. **Pull the splits calendar** for each ticker via `/v3/reference/splits?ticker={t}&execution_date.gte=...`. If any ex-date falls in the window, flag `corp_action_overlap` and populate the `corp_action` substructure with ratio and the post-adjustment quantity. This is informational; DTCC handles the share-count delivery automatically. 6. **Check half-day settlement**. If `computed_settlement_date` is in the holiday calendar with `status: "early-close"`, flag `half_day_settlement` and populate `session_info` with the close time and the DTCC cutoff time (typically 12:30 ET). 7. **Emit JSON and rendered output**. Only trades with at least one reason code appear. Summary block tallies counts by reason and reports the settlement window date range. ## Foundations used - [`massive-api-patterns`](../massive-api-patterns) for REST auth and rate limiting ## Endpoints used - `GET /v1/marketstatus/upcoming` (holiday + half-day calendar, one pull per run, cached) - `GET /v3/reference/dividends` (one paginated call per ticker; filtered to ex-dates in the settlement window) - `GET /v3/reference/splits` (one paginated call per ticker; same filter) All three are in Stocks Basic. The free tier's 5-calls-per-minute cap makes a 20-trade file take roughly 10 minutes; any paid tier eliminates the wait. ## Example ```bash # Trade file with 12 rows cat examples/sample-trades.csv # Invoke from Claude Code # > /t+1-settlement-prep examples/sample-trades.csv ``` The skill streams findings as it walks each trade, so the operator sees BREAK blocks as they're computed instead of waiting for the full report. ## Doesn't handle (yet) - **Symbol changes and delistings.** A trade in a ticker that changes symbol or delists between trade and settlement still settles correctly, but operations needs the new identifier. Detecting this requires reading `/v3/reference/tickers` over the window and comparing `last_updated_utc` to the trade date. Deferred to v2 of the skill. - **Cash-vs-margin reconciliation.** The skill flags ex-dividend exposure as a dollar impact but does not project the account-level cash delta. That's the cash-management system's job. - **Locate-file ingest.** The skill flags every SHORT row for locate confirmation. An operator with a CSV export of the prime broker's locate file can extend the skill with a second optional input to auto-confirm; today's v1 is a prompt, not a check. - **International equities.** Settlement calendars in EU (T+1 from October 2027), Japan (T+1 since 2024), India (T+0 in pilot) are different. The skill assumes US equities only. - **Options assignment cash flow.** OCC delivery on an assigned option settles T+1 like the underlying, but the workflow is different (premium debit, share delivery, exercise notice). A future `options-settlement-prep` skill would handle that. Add these in a PR if you need them. The calendar walking and ref-data pulls carry over.