Sleeper Fantasy Football MCP 2026

An MCP server that helps an AI agent run a Sleeper fantasy football team from draft night through the championship. Sleeper is the read-only source of league state; recommendations, draft queues, decision history, and model data are stored locally in SQLite.

What it does

• Discovers your league, roster, and draft from one Sleeper username or user ID.

• Syncs rosters, drafts, picks, matchups, transactions, players, and league history.

• Imports FantasyPros rankings, ADP, projections, injuries, and news.

• Recommends draft picks and estimates who may survive to your next pick.

• Maintains a conflict-safe local draft queue.

• Optimizes lineups and analyzes waivers, FAAB, trades, and season strategy.

• Learns descriptive manager tendencies from historical league behavior.

• Preserves source snapshots, recommendations, actions, and outcomes for later evaluation.

The models expose their inputs and uncertainty. Heuristic survival, FAAB, and championship estimates are not presented as calibrated facts.

Requirements

• Python 3.12+

• uv

• A Sleeper username or user ID

• A FantasyPros API key for rankings and projections

Setup

uv sync
cp .env.example .env

Edit .env:

FF2026_SLEEPER_USER_ID=your-sleeper-username
FF2026_FANTASYPROS_API_KEY=your-api-key

Start the stdio MCP server:

uv run --env-file .env ff2026-mcp

State is stored in .data/ff2026.sqlite3. Credentials are read only from the environment and are excluded from source control.

MCP configuration

{
  "mcpServers": {
    "ff2026": {
      "command": "uv",
      "args": [
        "--directory",
        "/absolute/path/to/mcp-ff2026",
        "run",
        "--env-file",
        ".env",
        "ff2026-mcp"
      ]
    }
  }
}

First run

Ask the agent to perform these operations:

1. initialize_season discovers and stores the league, roster, and draft defaults.

2. get_season_context confirms the selection.

3. sync_fantasypros imports preseason rankings and projections using week 0.

4. get_provider_status reports unresolved player identities.

5. sync_league_history imports previous seasons for manager analysis.

If the account has multiple leagues, initialize_season returns the choices instead of guessing.

During the draft

1. Run refresh_decision_inputs with week 0.

2. Read get_draft_state and stop if it reports stale data.

3. Use recommend_draft_pick and review the alternatives and survival ranges.

4. Update the local queue with set_draft_queue_entry.

5. Record the chosen action, sync the draft, and repeat.

No tool makes picks or other changes in Sleeper.

During the season

Refresh inputs each week, then use the lineup, waiver, trade, value-change, simulation, and season strategy tools as needed. Record actions and outcomes so calibration reports can evaluate the system prospectively.

Create a transactionally consistent backup with:

uv run --env-file .env ff2026-backup

Development

uv run ruff format --check .
uv run ruff check .
uv run mypy
uv run pytest

Detailed design and contracts:

• Architecture

• Data model

• MCP tool surface

• Implementation plan

• Architecture decision

Additional data sources must be licensed for your use. Boris-style tiers are treated as a FantasyPros-derived benchmark, not as independent evidence.