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

Annotations already declare this is a non-read-only, non-destructive, closed-world write, so the safety bar is partly covered. The description usefully adds visibility scope ('as the user, for everyone on the trip to see') and notification behavior for mentions, but says nothing about whether the comment can later be edited or removed, duplicate handling, or authorship constraints.

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?

A single front-loaded sentence starting with the action, with each parenthetical hint carrying real routing information. It is slightly dense with nested parentheses, but no sentence is filler.

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?

With an output schema present, return values need no explanation, and the description covers both target contexts and audience/notification scope for a five-parameter write tool. The remaining gap is not spelling out that exactly one of activityId or pinId must be supplied.

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 coverage is only 40%, and the description compensates by explaining activityId and pinId with their source tools, plus the visible/mention semantics. However, it leaves the body parameter's content expectations and the either/or requirement between activityId and pinId implicit, so the 2000-character body and mutually-exclusive target choice are never stated.

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-plus-resource ('Says something on an activity ... or a wishlist pin') and disambiguates the two targets by naming the source tool for each (get_plan, get_wishlist). An agent can tell exactly what gets created and where, distinguishing it from siblings like add_activity or add_to_wishlist.

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?

Frames the intended use ('a question for the group, or an answer to one') and names the upstream tools that supply each identifier, which implies the preconditions for calling it. It does not explicitly say when to prefer ask_poll/answer_poll or other siblings, but the activity/pin context is clear enough to route correctly.

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