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

With no annotations, the description carries the behavioral burden and does so well: it discloses real-time unsold capacity, the ordering heuristic, and the key fields returned, including a cross-reference to estimate_ad_cost. It does not disclose auth requirements, rate limits, or pagination, but those are minor for a read-style listing tool.

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?

Two tight sentences with no filler: the purpose and ordering are front-loaded, and the second sentence compactly enumerates the return fields and the quoting call. Every clause adds useful information.

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?

Although there is no output schema, the description explains what each returned tender carries, which is sufficient for an agent to understand the response shape. With three optional self-describing parameters, the tool is simple enough that no critical calling information is obviously 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 coverage is 100%, with limit, sport, and format each already described with enums and defaults. The description adds no new meaning about these input parameters beyond what the schema provides, so the baseline 3 is appropriate.

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 uses a specific verb ('List') and a clear resource ('slots with real unsold capacity right now'), plus a precise ordering rule ('by how close they are to selling out'). It distinguishes itself from siblings like estimate_ad_cost and submit_programmatic_bid by focusing on inventory discovery, not pricing or bidding.

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 implies the tool is for finding currently available, unsold inventory and even points to estimate_ad_cost for quoting. However, it does not explicitly state when to prefer this over sibling tools like check_neuron_inventory or submit_programmatic_bid, nor does it mention any exclusions or limitations.

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