ebay_bulk_create_ads_by_listing_id

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

The description's 'Bulk create' aligns with readOnlyHint=false and clarifies that this is a mutation that creates ads, not a read operation. However, it does not disclose additional behavioral traits such as whether the operation is asynchronous, whether partial failures occur, what side effects are produced, or any rate-limit/batch constraints. With annotations providing only a read-only flag, the description adds minimal behavioral context beyond the mutation type.

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, front-loaded sentence that contains the essential action ('Bulk create ads'), the key ('by listing id'), and the API context. There is no filler or redundant restatement of the tool name, and every word contributes to identifying the operation.

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?

Given the tool's nested request object, the absence of an output schema, and the lack of any usage or behavioral guidance, the one-sentence description is not complete enough for an agent to confidently invoke the tool. The agent cannot tell how to structure the requests array, whether bidPercentage is required, what the relationship between adGroupId and listingId is, or what response format to expect.

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 the description is not required to explain the top-level parameters. The description itself adds no parameter-level meaning: 'request' is only described as 'Bulk create ads by listing id request body' and campaignId as 'campaignId required endpoint parameter'. Nested fields like adGroupId, listingId, and bidPercentage are left entirely to the agent to infer, but the high schema coverage keeps this at baseline.

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 states a specific verb ('create'), a specific resource ('ads'), and a specific selection key ('by listing id'), which clearly distinguishes this tool from siblings like ebay_bulk_create_ads_by_inventory_reference and ebay_create_ad_by_listing_id. It also identifies the API domain ('eBay Marketing API'), leaving no ambiguity about what operation is performed.

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 does not provide any guidance about when to choose this tool over alternatives. It does not mention that single-ad creation should use ebay_create_ad_by_listing_id, or that inventory-reference-based bulk creation should use ebay_bulk_create_ads_by_inventory_reference. The 'bulk' and 'by listing id' wording implies the use case, but no explicit exclusions or alternative conditions are given.

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