Loading ToolBench
This server has well-structured tool definitions with explicit schemas and descriptions. All 15 tools are clearly named with action verbs (get_*), have non-empty descriptions (ranging 60-250 chars, within the 10-1024 baseline), and include input parameter schemas with type definitions and descriptions. However, there are significant gaps in error handling guidance, output schema documentation, and parameter validation details. Parameter descriptions are functional but could be more prescriptive about constraints. No tool annotations (readOnlyHint, destructiveHint, idempotentHint) are present. Most tools are READ_ONLY (appropriate) but this is not formalized in the schema layer. The descriptions accurately convey WHEN to use each tool (e.g., 'Call get-league-names-for-user before any league-specific operations') which is strong. Output structures exist in the code but are not formally documented in the tool registration. The server follows the verb_noun naming convention well and accepts human-friendly identifiers (username, leagueName) as required by pattern:chat-data-model.
Analyzes the bench vs starters for a given matchup week to see if making different lineup decisions could have changed the outcome
Gets the current week number for the nfl season.
Retrieves all historical matchups between two users in a league across multiple years
Retrieves all fantasy football league names associated with a Sleeper username. Use this tool to verify league names mentioned by users. When a user references a league name that doesn't exactly match any returned names, select the closest match from this list or inform the user about valid league names. This tool should be called before any league-specific operations to ensure the correct league is targeted.
Retrieves a league's playoff structure and schedule, mapping playoff rounds (like quarterfinals, semifinals, finals) to their corresponding week numbers. Use this tool to determine which NFL week corresponds to specific playoff rounds based on the league's settings.
Retrieves the roster details for the league (i.e. How many starting roster slots and the type of those roster slots.).
No tool annotations (readOnlyHint, destructiveHint, idempotentHint) present. All 15 tools are READ_ONLY but this is not formally declared in the tool schema, forcing LLMs to infer safety from descriptions alone.
Output schemas are not formally documented in tool registration. While the code returns well-structured responses (markdown text in response.content), callers cannot see the response schema in advance. This violates pattern:response-shaper which requires documented output types so LLMs can plan downstream calls.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-22 | D | 58 | 2026-07-28+ | v2 |
| 2026-03-09 | F | 0 | - | v1 |
Gets the detailed scoring settings for a league
Gets the general settings, wavier settings, and taxi settings (if dynasty league) for a given league
Gets the bench players for the matchup week for the given username, league, week, and year
Gets the matchup for the user given the league name, username, week, and season year
Gets the starters for the matchup week for the given username, league, week, and year
Gets the playoff bracket for a given league, year, and bracket type (winner's or loser's bracket for double-elimination leagues)
Gets the playoff results/history for a league across one or more years
Gets the current top 5 trending players based on waiver adds, drops, or both
Gets the players on the user's roster that are currently trending
Error handling does not include recovery guidance. Tools return isError=true with plain text messages (e.g. 'Failed to retrieve NFL state data', 'Unable to fetch the most recent leagues'). Per pattern:recovery-guide, errors should suggest next steps: 'User not found. Try search_users() with a partial name.' Current errors give LLM no actionable path forward.
Parameter 'year' descriptions mention examples ('2022', '2022-2024', '2022,2023,2024') rather than formal format constraints. Per pattern:constrained-input, this should use a regex pattern or enum+description hybrid. LLMs may hallucinate invalid formats like '2022-2024 and 2025' or '2022/2024'.
Parameter descriptions lack explicit range/format constraints. E.g., 'week' param has no min/max bounds stated in the description.
No pagination support documented. Tools like get-trending-players return 'top 5' but don't expose limit/offset parameters or document how to fetch beyond the 5. Per pattern:paginated-result, discovery tools should accept limit and provide cursors or offsets.
Tool responses return plain markdown text within response.content[0].text. While human-readable, this makes it hard for LLMs to extract structured data downstream (e.g., extracting player names or scores for further analysis). Per pattern:response-shaper, prefer JSON objects with typed fields over unstructured markdown.