Yahoo Fantasy Baseball

26 tools. 6 can modify or destroy data without limits.

1 destructive tool with no built-in limits. Policy required.

Last updated:

6 can modify or destroy data
20 read-only
26 tools total

Community server · catalogue entry checked 07/07/2026 · full schemas captured for 23 of 26 tools

How to control Yahoo Fantasy Baseball ↓

What Yahoo Fantasy Baseball exposes to your agents

Read (20) Write / Execute (5) Destructive / Financial (1)

What Yahoo Fantasy Baseball costs in tokens

3,977 tokens of tool definitions, loaded on every request
2.0% of a 200k context window
348 heaviest tool: search_players
Critical Risk

The most dangerous Yahoo Fantasy Baseball tools

6 of Yahoo Fantasy Baseball's 26 tools can modify, destroy, or commit something on every call — and an agent calls them with no built-in limits.

How to control Yahoo Fantasy Baseball

PolicyLayer is an MCP gateway — it sits between your AI agents and Yahoo Fantasy Baseball, and nothing reaches the server without passing your rules. These are the rules we recommend:

Deny destructive operations
{
  "fantasy_logout": {
    "deny_if": [
      {
        "conditions": [],
        "on_deny": "Blocked by default. Requires approval."
      }
    ]
  }
}

Destructive tools should never be available to autonomous agents without human approval.

Rate limit write operations
{
  "add_drop_player": {
    "limits": [
      {
        "counter": "add_drop_player_per_hour",
        "window": "hour",
        "max": 30,
        "scope": "grant"
      }
    ]
  }
}

Prevents bulk unintended modifications from agents caught in loops.

Cap read operations
{
  "analyze_player_stats": {
    "limits": [
      {
        "counter": "analyze_player_stats_per_minute",
        "window": "minute",
        "max": 60,
        "scope": "grant"
      }
    ]
  }
}

Controls API costs and prevents retry loops from exhausting upstream rate limits.

  1. Create a free account and register Yahoo Fantasy Baseball — nothing to install.
  2. Add these rules — paste them, or build them visually. Tune the limits to your setup.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
ENFORCE POLICY ON YAHOO FANTASY BASEBALL →

Instant setup, no code required.

All 26 Yahoo Fantasy Baseball tools

READ 20 tools
Read analyze_player_stats Fetch and aggregate advanced statistics for a single player from multiple authoritative sources: MLB Stats API Read analyze_roster_stats Fetch advanced stats (Statcast, expected stats, FanGraphs) for a batch of rostered players. Accepts at most 10 Read fantasy_status Report whether Yahoo Fantasy is set up and what the next step is. Use this for 'fantasy status'. Read get_league Get a league's teams, settings, and current standings. Defaults to the configured league when leagueKey is omi Read get_league_scoring_categories Return the stat categories used for scoring in this league (e.g. R, HR, RBI, SB, AVG for batting; W, ERA, WHIP Read get_matchups Get the league scoreboard (all head-to-head matchups). Pass a week to view a specific week, otherwise the curr Read get_player_stats Get stats for one or more players on a specific date. Player keys look like 431.p.10642. Read get_roster Get a team's roster for a date — each player's roster slot (starting position or BN/IL bench), starting status Read get_roster_stats Get a team's roster with each player's Yahoo stats for a given date. Like get_roster but heavier — use get_ros Read get_standings Get the league standings table — each team's rank, win/loss record, games back, playoff seed, and season categ Read get_team_matchups Get a team's matchups across the season, or only the listed weeks when weeks is provided. Read get_team_stats_season Get a team's aggregated stats for the whole season. Read get_team_stats_week Get a team's aggregated stats for a specific scoring week. Read get_teams Get stats, standings, and matchups for every team in a league. Pass explicit teamKeys to limit the set, otherw Read get_transactions Get recent transactions (adds, drops, trades) in a league. Pass teamKey to filter to a single team's transacti Read list_leagues List all fantasy leagues (and game weeks / stat categories) for the logged-in Yahoo account. Use this to disco Read list_players List league players (including free agents) in ranked order with their name, position, eligible positions, sta Read list_probable_starters List every probable starting pitcher across MLB for a date, with each one's opponent, home/away, and game star Read rank_players Rank league players (including free agents) by a sort key. sort is a stat id or one of AR (actual rank), OR (o Read search_players Find players by name (full or partial) and resolve them to player keys. This is the way to turn a name the use

Related servers

Other MCP servers with similar tools — same risk classification, starter policies for each.

Questions about Yahoo Fantasy Baseball

Can an AI agent delete data through the Yahoo Fantasy Baseball MCP server? +

Yes. The Yahoo Fantasy Baseball server exposes 1 destructive tools including fantasy_logout. These permanently remove resources with no undo. PolicyLayer blocks destructive tools by default so they never reach the upstream server.

How do I prevent bulk modifications through Yahoo Fantasy Baseball? +

The Yahoo Fantasy Baseball server has 5 write tools including add_drop_player, fantasy_authorize, fantasy_login. Set a rate limit in your policy -- for example, 10 calls per hour prevents an agent from making more than 10 modifications per hour. PolicyLayer enforces this at the gateway, before calls reach Yahoo Fantasy Baseball.

How many tools does the Yahoo Fantasy Baseball MCP server expose? +

26 tools across 4 categories: Destructive, Execute, Read, Write. 20 are read-only. 6 can modify, create, or delete data.

How do I enforce a policy on Yahoo Fantasy Baseball? +

Register the Yahoo Fantasy Baseball MCP server in PolicyLayer, apply the suggested rules above (adjust the limits to your use case), and point your AI client at the PolicyLayer proxy URL instead of the server directly. Your agents keep the same tools; PolicyLayer evaluates every call against policy before it executes. Nothing to install, live in minutes.

Enforce policy on every Yahoo Fantasy Baseball tool call.

Deterministic rules across all 26 Yahoo Fantasy Baseball tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

Instant setup, no code required.

26 Yahoo Fantasy Baseball tools catalogued and risk-classified — across an index of 46,500+ MCP servers.

// WHERE THIS COMES FROM

These policies come from Yahoo Fantasy Baseball's registry record.

The record behind this page: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.

Teams ship this data inside their own products. See what a licence covers →

// GET IN TOUCH

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