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

Annotations only declare non-read-only, non-idempotent, non-destructive, open-world. The description adds the material behavior beyond that: authenticity is required, submissions are final and uneditable, and the data state at submission time is sealed as evidence. This is exactly the irreversible-write context an agent needs and that the annotations alone do not convey.

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?

The key requirement and the immutability constraint are front-loaded, which is the right ordering for an irreversible write. The bilingual restatement duplicates content already given in Korean, adding length without new meaning, but nothing is genuinely wasted.

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 no output schema, the description still covers the two things an agent most needs: the key prerequisite and the fact that submission cannot be undone. It does not describe the response payload or failure modes (e.g., duplicate submission error), which is the main remaining gap for a mutation tool.

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 100%, so the schema already documents question_id (an arena_questions index) and probability (0–1). The description restates the 0–1 range and the one-per-question cardinality but adds no format or validation detail 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?

The description says it submits a probability forecast for an arena question, with a specific verb (submit) and resource (arena question forecast). This is clearly distinct from sibling readers such as my_arena_forecasts or arena_questions, though no sibling is named explicitly.

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?

The 'one per question, cannot be edited' constraint implicitly tells the agent to be deliberate about when to call, and the [key required] tag surfaces a prerequisite. However, it never states when to prefer this tool over looking at existing forecasts or how to recover if a forecast already exists.

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