compare_players

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description discloses important behavioral details: it explains optional parameters, env var fallback (ESPN_LEAGUE_ID, ESPN_YEAR), defaults (9-cat), and authentication requirements for private leagues (espn_s2, swid). However, it does not explicitly state that this is a read-only operation or describe error handling, but the read nature is evident from the verb 'compare.' This provides meaningful context beyond schema.

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?

The description is structured with an overall summary, Args list, and Returns mention. Each line adds value, but the list format makes it longer than necessary for a simple tool. Still, it is well-organized and not padded; a score of 4 reflects appropriate sizing with a slight efficiency loss from the docstring format.

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?

Given that there is no output schema and no annotations, the description covers all six parameters, their defaults, and auth, and summarizes the return as a dictionary with winner by category. It does not detail edge cases like invalid player IDs or what 'winner' means, but it is sufficient for the tool's moderate complexity.

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?

The schema has zero parameter descriptions (0% coverage), so the description's Args section is the sole source of parameter semantics. It explains player_ids as ESPN IDs, league_id with env var fallback, year with default, categories with default, and auth cookies—far exceeding schema info.

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?

The description begins with a clear, specific verb phrase 'Compare multiple players across statistical categories,' identifying the resource (players) and scope (statistical categories). This distinguishes it from sibling tools like get_player_stats that focus on single players or league-level queries, and from advisory tools like analyze_trade_proposal.

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 implies usage by stating 'Compare multiple players,' but it offers no explicit guidance on when to choose this over alternatives. There is no mention of exclusions, such as 'use get_player_stats for a single player's stats.' Usage context is inferred rather than stated, earning a 3.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.