espnfantasy_player_news

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

Annotations already declare readOnlyHint and idempotentHint, so the description need not re-state safety. It adds valuable behavioral context: the return structure (news feed with fields), auth behavior ('works without a key; ESPN_FANTASY_COOKIE unlocks more'), and the example input. This goes beyond the annotations without contradicting them, though it does not detail rate limits or pagination behavior.

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 efficiently organized: one-sentence purpose, a compact return schema, an example, and an auth note. No filler or redundancy; every segment earns its place.

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 only 2 parameters, no output schema, and rich annotations, this description is complete. It covers purpose, usage, parameters (via example and source context), return format, and auth. The safety profile is handled by annotations, and the remaining operational details are addressed.

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?

Input schema covers both params with descriptions (100% coverage). The description adds an example ({"game": "ffl", "playerId": 3139477}) and clarifies playerId as 'from espnfantasy_players or a roster entry' (schema says 'ESPN player id'). These additions provide practical context beyond the schema, but the schema already carries most semantic weight.

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 clearly states it provides 'Recent fantasy news items for one player' with a specific focus on 'injury/usage blurbs that drive start-sit calls.' This is a specific verb+resource+scope that distinguishes it from general news tools like espn_news and other espnfantasy tools. The mention of 'one player' specifies the resource granularity precisely.

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 the use case (getting player-specific fantasy news for start-sit decisions) and includes an example call. It does not explicitly name alternatives or provide 'when not to use' guidance, but the single-player scope makes the usage context clear. Lacks explicit exclusion such as 'for team-wide news use espn_news instead.'

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