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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful behavior beyond them: a nonexistent slug returns 404/not-found, and an existing tournament with zero questions returns an empty list rather than an error — an important distinction for the agent to handle.

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, front-loaded sentences: what it lists, the parameter behavior, the error/empty semantics, and the sibling routing. Zero padding and no restated boilerplate.

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-shape explanation is unnecessary, and the description still covers the failure modes (404, empty list) and the cross-tool handoff. Nothing an agent needs 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%, so slug and limit are already documented; the default/cap restatement is redundant. But the description adds a detail the schema does not: the slug field also accepts a numeric project id, which changes how the agent can call it. That is real value above baseline 3.

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 (public question rows) with explicit scope (belonging to one tournament or question-series slug), and it names the sibling tool metaculus_question to contrast the single-question case. An agent can distinguish it from metaculus_questions/project_questions 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?

It routes the agent to metaculus_question for drilling into a single returned question, which is clear context for follow-up. However, it gives no guidance on when to prefer this tool over the nearby siblings metaculus_project_questions, metaculus_category_questions, or metaculus_questions — that selection is left implicit.

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