mlb_search_playersSearch MLB players by name to retrieve their IDs, teams, and positions. Use it to identify the right player for stats, rosters, or team lookups.
Search for players by name. Returns matching players with their IDs, teams, and positions.
| Name | Required | Description | Default |
|---|---|---|---|
| names | Yes | Player name(s) to search for | |
| fields | No | Keys to keep (comma-separated). | |
| sportId | No | Sport ID (1=MLB) |
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"
+}v1.3.0Input schema / additionalPropertiesRemoved value: -falsev1.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so the safety profile is covered. The description adds useful return content (IDs, teams, positions), which is helpful given there is no output schema, but it says nothing about match behavior (partial vs exact, case sensitivity) or result limits.
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?
Two short sentences with zero waste; the core action is front-loaded and the return summary follows immediately. Nothing is padded or redundant.
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?
For a simple search tool with a fully-covered schema and annotations carrying the safety profile, the description is nearly complete. It covers purpose and return shape but omits search semantics (partial matching, multi-name handling), which an agent would benefit from knowing.
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 all three parameters (names, fields, sportId) are already documented in the schema. The description adds no syntax, format, or matching detail beyond what the schema provides, making the baseline 3 correct.
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 (search) and resource (players), scoped to MLB via the name/title. It clearly implies lookup-by-name versus the sibling mlb_get_player, but the description itself never explicitly distinguishes them, so it stops short of a 5.
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 offers no when-to-use guidance and names no alternatives, despite many overlapping siblings (mlb_get_player, mlb_get_team_roster, sportsdb_search_players). An agent must infer that this is the fuzzy-name entry point while mlb_get_player is the by-ID lookup.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.