Add a product to a board (guaranteed real image)

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

With no annotations provided, the description carries the full burden and excels: it discloses the image resolution pipeline, rejection criteria, web search fallback, and the 'NEVER rejects a product' guarantee. It also explains what happens when no image is found, covering edge cases comprehensively.

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 description is a single dense paragraph, front-loaded with the main purpose. It is somewhat long but every sentence contributes information about behavior or edge cases, with no redundancy.

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?

Despite no output schema or annotations, the description is thoroughly complete for this tool's complexity. It covers the full workflow, failure modes, and guarantees, giving an agent all necessary context to invoke it correctly.

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 baseline is 3, but the description adds meaningful context beyond the schema—e.g., how fallback_urls are used, the role of title as block title, and the behavior of the URL resolution. This elevates the value.

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 clearly states it adds a product to a channel with a real product photo, using specific verbs and a distinct resource. It differentiates from sibling tools like arena_add_block and arena_add_products by emphasizing image resolution and product-specific behavior.

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 description provides clear context on how the tool operates, including image resolution and fallback behavior, but does not explicitly name alternatives or state when not to use it. The context is strong enough that an agent can infer when this tool is appropriate.

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