sleeper_get_leagueRetrieve a Sleeper fantasy football league's settings, scoring rules, roster positions, and status using its league ID.
Get details for a Sleeper league (settings, scoring, roster positions, status).
| Name | Required | Description | Default |
|---|---|---|---|
| fields | No | Keys to keep (comma-separated). | |
| league_id | Yes | League id (from sleeper_get_user_leagues) |
Changes observed during successful MCP inspections.
v1.4.1Input schema / $schemaRemoved value: -"http://json-schema.org/draft-07/schema#"Input schema / properties / fieldsAdded value: +{
+ "description": "Keys to keep (comma-separated).",
+ "type": "string"
+}v1.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so safety and repeatability are covered. The description adds the useful detail that the payload includes settings, scoring, roster positions, and status, but says nothing about response shape, auth requirements, or rate limits — acceptable given annotation coverage but not rich.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with the verb, resource, and returned content; no filler sentences, no redundancy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
There is no output schema, so the description's enumeration of returned content areas does necessary work by telling the agent what a call yields. Combined with the 100%-covered input schema, an agent has enough to invoke it correctly, though it lacks any statement of scope limits or error behavior.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so both parameters are documented in the schema, including the provenance of league_id. The description adds no syntax or format detail for the 'fields' key-filtering parameter, so this is baseline territory.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource ('Get details for a Sleeper league') and enumerates the content areas (settings, scoring, roster positions, status), which distinguishes it from roster/user/matchup siblings. It does not explicitly name or contrast with the closest siblings (sleeper_get_league_rosters, sleeper_get_league_users), so it stops short of full differentiation.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description itself gives no when-to-use or when-not-to-use guidance. The only usage signal is indirect: the league_id schema description points to sleeper_get_user_leagues as the source of the id, which implies the intended workflow without stating it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.