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

Annotations already establish this as a safe, non-destructive local read (readOnlyHint=true, openWorldHint=false), so the description's extra value is the disclosure that premium games are listed and flagged rather than silently filtered. That is useful behavioral context beyond the annotations, though rate limits or pagination behavior are not addressed.

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 tightly written sentences, with the resource and returned fields front-loaded and the usage guidance immediately after. No filler or redundant restatement of the title.

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 read-only one-parameter list tool, the description covers purpose, returned fields, and the downstream workflow, while the output schema handles return shape. Nothing needed to invoke it correctly 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?

Schema description coverage is 100% and the single include_premium parameter is fully documented in the schema, so the schema carries the burden. The description's mention of 'whether it needs a paid plan' corroborates but does not extend the schema's default/flagging semantics.

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 (List) and resource (team-building games on Fun Friday) and enumerates the returned attributes (name, description, ideal group size, paid-plan flag). It is clearly distinguishable from the mutating siblings such as funfriday_create_session and funfriday_create_pack.

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?

Explicitly names two use cases — answering 'what could we play?' and picking a game_type before calling funfriday_create_session — which routes the agent to the correct follow-up tool. This is a concrete when-to-use with a named downstream alternative.

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