---
name: set-lineup
description: This skill should be used when the user asks to "set my lineup", "start him for me", "swap him into my flex", "update my lineup on Yahoo", "fix my lineup before kickoff", "apply my lineup changes", or wants a lineup change actually applied on their fantasy platform. Drives the user's own logged-in browser session to set the lineup - Yahoo first, with ESPN and Sleeper variants. Always pauses for explicit confirmation before committing. Not for deciding who to start in the first place (lineup-strategy start-sit), cut decisions (waiver-wire drop-candidates), or add/drop transactions (roster-ops submit-waiver-claim).
---

# Set Lineup (Browser Playbook)

Decide the best starting lineup, then set it on the user's platform through their own logged-in browser session. Two phases, one hard gate: **never save a lineup change without explicit user confirmation.**

## Ground rules (all roster-ops skills)

- **The user's session is the auth.** Never ask for, read, store, or type usernames, passwords, or 2FA codes. If a login page, 2FA challenge, captcha, or "unusual activity" interstitial appears **at any point**, stop immediately and hand the browser back — do not attempt to solve or dismiss it. Never interact with password-manager UI, autofill prompts, or "stay signed in" dialogs; clicking an autofill suggestion is entering a credential. After any re-authentication, restart from the beginning of the execution phase and re-verify the league and team landmarks — do not assume the account, league, or in-progress form survived. If you were mid-transaction, first determine from the page whether it went through.
- **Never run unattended.** These skills require a human present to confirm each transaction. Do not run them on a schedule, in a loop, or as a background task. If asked to automate a recurring roster move, decline the automation and offer a reminder instead. Driving your own logged-in session interactively, with a human approving each action, is what keeps this within what platforms tolerate — it stops being that the moment nobody is watching.
- **Use the UI, never the API.** Do not call platform endpoints directly, execute page JavaScript, or use shell tools to reach the platform, even when the interface is uncooperative. If the UI cannot do it, stop and tell the user.
- **Act at human pace.** No rapid-fire clicking or searching. If a captcha or rate-limit page appears, stop and hand back — never attempt to work around one.
- **Handle platform dialogs deliberately.** A confirmation dialog raised as a direct result of a click the user already approved is part of that approved action: read it, verify it describes that transaction and nothing more, then accept. A dialog describing anything unapproved (an extra drop, a different player) is a stop — dismiss it and report its wording verbatim. Never accept a dialog you have not read. Cookie banners and promo overlays are not transactions; dismiss and continue.
- **Budget your actions.** If you have taken roughly 15 actions without reaching the intended screen, stop and hand back with a description of where you are, rather than continuing to hunt.
- **Navigate by goals and landmarks, not memorized selectors.** Platforms redesign constantly; find things by their visible text and structure ("the roster table", "the section labeled Bench"), and read the page when unsure.
- **Confirmation gate**: before any click that commits a change, show the user exactly what is about to change and wait for an explicit yes. Everything before that (navigation, reading, opening dialogs) is fair game.
- **The confirmation must post-date the summary.** It has to arrive in a user message *after* the summary read off the actual page, in the same turn as the click. An instruction given before the browser was open — including "and submit it" or "just do it" — authorizes building the change, never committing it. A reply that alters any term ("yes, but bench Moss instead") is a **modification, not a confirmation**: apply it, re-read the page, present a fresh summary, ask again.
- **Never retry a commit click.** If an action's result is unclear, re-read the page to find out whether it landed. Retry only on positive evidence the change is *absent*. If the page is ambiguous or mid-update, wait and re-read — never click again.
- Browser tooling: use the available browser-automation tools (e.g., Claude in Chrome). If none are available in the session, say so and fall back to advising the moves for the user to click themselves.

## Phase 1: Decide the lineup

1. Read `leagues.md` from the project root first — the fields that matter here are platform, scoring, starting slots, and playoff weeks. If the file is missing or those fields are blank, ask for them directly and suggest running the `fantasy-league-setup:league-config` skill to persist the answers. If `leagues.md` defines more than one league, use the one marked `(default)` unless the user names another.
2. Navigate to the roster (Phase 2 steps 1–2) and **read the current lineup from the page** — the page is the ground truth, not memory of past conversations.
3. Recommend a lineup: fill required slots by expected points for this league's scoring; check injury/questionable tags and bye weeks shown on the page; flex goes to the best remaining eligible player. Where two options are close, say it's close and why the edge goes where it does. Honor overrides — the user's call wins.
4. Present the recommendation as a before/after list of only the slots that change. If nothing should change, say so and stop.

## Phase 2: Execute on Yahoo

1. **Get to the team**: first check whether the user already has a tab open on the platform and use it — navigating fresh discards in-progress state and routes through the provider's general shell, where consent walls and the user's personal account details appear. Otherwise go to the sport-scoped entry point (`football.fantasysports.yahoo.com`) rather than browsing through the provider homepage. Ensure a desktop-width viewport (≥1280px) before starting; narrow windows change the swap mechanism entirely. Open the team matching the league name in `leagues.md`. Landmark: a page header with the team name and a navigation row containing "Roster".
2. **Open the roster for the right week**: click Roster; verify the week selector shows the intended week. Landmark: a table of position slots (QB, RB, WR, TE, FLX/W-R-T, K, DEF) with a **Bench (BN)** section below the starters.
3. **Determine the commit model before touching any player.** Read the roster page and look for a Save/Submit/Apply control governing the roster. If there is none, **every swap commits immediately**. When it cannot be determined, assume immediate commit — that is the fail-safe assumption, and it is the working assumption for Yahoo and Sleeper.
4. **⛔ CONFIRMATION GATE** — placed according to the commit model:
   - **Immediate-commit UI (assume this unless a Save control is visible):** the gate comes **before the first swap** and covers the whole set. Restate every change ("Starting Okafor over Trask at RB2; Pruitt in for Vasquez at TE"), get an explicit yes, and only then touch the first player. Once started, complete the entire approved set — a half-applied lineup can leave a slot empty, which scores zero and is worse than the lineup the user started with.
   - **Batched UI (a Save control exists):** stage all swaps, gate, then save. If the user declines, navigate away without saving and confirm to them that nothing changed.
5. **Swap players**: the goal is that player X ends up in slot Y. Depending on build and viewport this is a per-row position control that reveals eligible destinations, drag-and-drop of the row, or tap-source-then-tap-destination. Use whichever affordance is actually visible; if a row exposes no obvious control, read the page and describe its controls rather than guess-clicking. Locked players (games started) show a lock — skip them and tell the user.
6. **Verify**: re-read the roster page; confirm each intended player sits in the intended slot, and that no starting slot is empty. Report the final lineup. Clicking a control is not evidence it worked. If a swap is genuinely absent, retry that swap once; if verification stays unclear after two reads, stop and tell the user exactly what the page shows and where to check.

Note: if the league has Yahoo's **"Start Active Players"** auto-swap enabled, Yahoo may move players on its own. A lineup differing from what was set is not necessarily a failed swap — read before concluding, and never "correct" an auto-move without asking.

## Platform variants

- **ESPN** (`fantasy.espn.com`): Roster page uses per-player **Move** buttons → legal slots show **Here** buttons. Changes generally apply immediately per swap, so apply the confirmation gate *before each Move/Here pair*, not just at the end. Landmark: Starters table above a labeled Bench table.
- **Sleeper** (`sleeper.com`): open the league → Team/Roster. The web app is drag-or-tap: tap a starter, tap the bench player to swap. Swaps commit immediately — there is no Submit Lineup control to gate on, so gate **before the first swap** per step 4. Landmark: starters listed by slot at top, "Bench" list below.

## Failure handling

- Page doesn't match these descriptions: don't guess-click. Read the page, describe what's visible, and ask the user to point at the right control if still ambiguous.
- Player missing from roster page: the user may be in the wrong league (multi-league accounts) — check the league name landmark before anything else.
- Lineup locked (kickoff passed): report which slots are locked; offer to set the remaining days' players only.

## Example run (fictional)

"Set my lineup for week 9" → leagues.md says Yahoo, "Gridiron Gazette". Roster page shows TE Oren Vasquez on **bye** in the TE slot and RB Silas Okafor on the bench.

> Recommendation: TE Harlan Pruitt in for Vasquez (bye); Okafor over Trask at RB2 (lead role, +3.2 proj). Two swaps, nothing else moves. No Save control on this roster page, so each swap commits the moment I make it — confirming both up front. Set it? — *user: yes* — Both swaps applied, then verified by re-reading the page: Pruitt TE, Okafor RB2, Vasquez and Trask to bench. Lineup is legal — no empty slots, no byes starting.