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

Annotations declare a non-read-only, non-destructive, non-idempotent, open-world operation, and the description adds real behavior on top: duplicates are skipped case-insensitively and reported back, and input is capped at 100 names per call. It does not disclose auth expectations beyond 'private organizer link' or any error behavior for an invalid link, so it stops short of a 5.

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?

Four short sentences, front-loaded with the usage trigger, and every sentence carries a distinct fact: prerequisite, inputs, batching, dedupe, and scope exclusions. The parenthetical '(send more in further calls)' is the only mild echo of the schema.

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 still covers the prerequisite draw, the private link requirement, the batch ceiling, duplicate handling, and scope boundaries. For a two-parameter mutation tool with full annotation and schema coverage, nothing an agent needs before calling 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%, so both parameters are already documented in detail, including the 100-item cap, the per-item length expectation, and the /m/ pattern of the organizer link. The description restates the batch limit and identifies manage_url as private, but adds no syntax or format meaning beyond the schema, so the baseline 3 applies.

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 and resource ('add entrant names to a draw') and anchors it to the sibling that creates that resource ('a draw made with create_prize_draw'). An agent can distinguish it from draw_winners and show_draw_results without opening any schema.

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?

Gives an explicit trigger ('Use this when the organizer wants to add entrant names'), a timing condition ('before the winners are drawn'), and explicit exclusions ('Does not draw; does not remove names') that route the agent to the sibling tools for those actions. Both when-to-use and when-not-to-use are covered.

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