List league players (including free agents) in ranked order with their name, position, eligible positions, status, and ownership (free agent or owning team) — but no stats. This is the light way to scan waiver/free-agent targets; once you have candidates, use analyze_player_stats or rank_players ...
AI agents call list_players to retrieve information from Yahoo Fantasy Baseball without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
| Parameter | Type | Required | Description |
|---|---|---|---|
sort | string | — | Stat id, or AR / OR / PTS |
count | integer | — | Number of players to return (max 25) |
start | integer | — | Pagination offset |
sortType | string | — | Ranking window |
leagueKey | string | — | League key; defaults to configured league |
Parameters from the server's own tool schema.
This tool performs data retrieval only—listing players and their metadata without modifying any game state, creating financial transactions, executing code, or deleting data. It is a pure query operation typical of fantasy sports league browsing, with minimal blast radius if misused by an AI agent.
From the tool's definition Tool description explicitly states it 'List[s] league players' and retrieves player information 'with their name, position, eligible positions, status, and ownership' with 'no stats'.
Attacks that exploit this kind of access
List league players (including free agents) in ranked order with their name, position, eligible positions, status, and ownership (free agent or owning team) — but no stats. This is the light way to scan waiver/free-agent targets; once you have candidates, use analyze_player_stats or rank_players for their stats. sort is a stat id or AR / OR / PTS. Returns up to 25 players per call; page with start. It is categorised as a Read tool in the Yahoo Fantasy Baseball MCP Server, which means it retrieves data without modifying state.
list_players accepts 5 parameters: sort, count, start, sortType, leagueKey. The full parameter table on this page comes from the server's own tool schema.
Register the Yahoo Fantasy Baseball MCP server in PolicyLayer and add a rule for list_players: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Yahoo Fantasy Baseball. Nothing to install.
list_players is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the list_players rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for list_players. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
list_players is provided by the Yahoo Fantasy Baseball MCP server (yahoo-fantasy-baseball-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
list_players is one line of Yahoo Fantasy Baseball's registry record.
The record carries the whole server: 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 →