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

Annotations already declare idempotent=true, destructive=false, and readOnly=false. The description adds genuinely useful non-obvious context: the deferred-effect contract ('no group is created until the exact card is confirmed'), which explains the preview/confirm two-phase flow that annotations cannot express.

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, and the core effect constraint is front-loaded in the second sentence. Nothing 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?

An output schema exists, so return values need not be described. However, for an 8-parameter mutation with 0% schema documentation, the description omits critical input semantics such as requestId's idempotency role and the capacity/title constraints, leaving the agent under-informed.

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 0% across 8 parameters, so the description carries the full burden, yet it only obliquely gestures at two of them ('public or private' -> visibility, 'gathering or group chat' -> kind). Required fields like requestId, title, and capacity limits (2-50) are unexplained anywhere.

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 (prepare) and resource (gathering or group chat), and the second sentence clarifies this is a preview step. However, it does not differentiate itself from nearby siblings like fitmeet_chat_prepare or fitmeet_group_confirm, and the phrase 'gathering or group chat' blurs which sibling owns which resource.

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?

'No group is created until the exact card is confirmed' implies the confirm step must follow, giving implicit usage context. But it never names the alternative tool (fitmeet_group_confirm) or states when to choose this over fitmeet_chat_prepare, leaving routing to inference.

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