nexus_get_favourite_games

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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds a valuable behavioral detail beyond those annotations: this call consumes the v2 GraphQL pool rather than the v1 REST rate-limit quota, which materially affects rate-limit planning. It also confirms the return shape is a JSON array.

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 compact and front-loaded: the main purpose appears in the first sentence, followed by a single high-value rate-limit note, then a concise return-format list. No filler or redundant wording.

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 this is a simple, parameterless read-only tool with supportive annotations and an output schema, the description provides enough context: what is returned, which GraphQL pool is used, and that it operates on the authenticated user's data. Nothing critical is missing.

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 tool takes zero parameters, so the schema fully covers parameter needs. The description's mention of the returned fields is not about parameters, but no parameter documentation is needed here. Baseline 4 for a zero-parameter tool is appropriate.

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 states a specific verb and resource: retrieve the authenticated user's favourite games. It also identifies the API version (v2 GraphQL), making it easy to distinguish from sibling tools like nexus_get_games, nexus_add_favourite_game, and nexus_remove_favourite_game.

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 scope is clear: this is for the authenticated user's favorite games. However, the description does not explicitly name alternatives, state when not to use this tool, or provide exclusion criteria versus related game-listing tools. Usage is mostly implied rather than explicitly routed.

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