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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so the safety profile is covered. The description adds meaningful context beyond annotations: Amazon-source fields, bounded pagination, diagnostics for unsupported product/entity pairs, SB target alias behavior, and the explicit constraint that agentcentral does not infer actions.

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 three sentences and front-loads the core purpose. The middle sentence is dense with parenthetical detail, but every clause earns its place by clarifying entity_type aliasing and supported SB target behavior for a 21-parameter tool.

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 complex 21-parameter schema, 100% schema description coverage, and an output schema, the description is largely complete: it covers purpose, read-only scope, pagination, diagnostics, and SB target aliasing. It lacks explicit when-to-use routing against sibling tools, but that is the only notable gap for an otherwise well-documented live entity-listing 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 description coverage is 100%, so the baseline is 3. The description adds semantic value beyond the schema by explaining that entity_type=target or negative_target routes SB keyword/product/category/theme targets through Common Campaign Management, and that keyword/negative_keyword aliases to KEYWORD targets and surfaces keyword text, match type, and bid.

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 (List) and resource (current Sponsored Products, Sponsored Brands, or Sponsored Display entity state) with a clear scope: directly from Amazon Ads API for verified read-only combinations. It does not explicitly name sibling tools such as get_sp_entities_live or get_sponsored_ads_report, but its broader ad-product coverage is distinguishable from those narrower sibling tools.

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?

Usage is implied by phrases like 'for verified read-only combinations' and 'diagnostics for unsupported product/entity pairs', which tell the agent this tool is for supported read-only entity-state queries. However, it does not explicitly say when to use this tool instead of alternatives like get_sp_entities_live, get_sd_campaign_performance, or get_sponsored_ads_report, leaving routing guidance incomplete.

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