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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds no behavioral context beyond that — no pagination/result-size behavior, no hints about needing a valid account/profile scope, and no indication of what happens when no portfolios exist.

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?

A single, front-loaded sentence with the verb and resource first. It is efficient and wastes no words, though the parenthetical explanation is slightly redundant for a domain-savvy agent.

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?

For a simple read-only list tool with annotations covering the safety profile and no output schema, the definition is minimally viable. However, with one of two parameters undocumented and no scoping or return-shape context, an agent still lacks what it needs to call this reliably in a multi-account environment.

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 only 50%: account_id has an (Italian-language) description, but profile_id has none. The tool description says nothing about either parameter, so it fails to compensate for the uncovered parameter and adds no meaning beyond the partial schema documentation.

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?

States a specific verb and resource ('List Amazon Ads portfolios') and even explains what a portfolio is ('groups of campaigns with optional shared budget'), which helps an agent understand the domain object. It doesn't name or differentiate against any sibling, but there is no competing list_portfolios tool, so ambiguity is low.

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?

There is no guidance on when to call this tool versus alternatives such as ads_list_profiles, ads_list_sp_campaigns, or ads_catalog_coverage. No prerequisites or conditions (e.g., needing an account context first) are stated, leaving routing entirely to inference from the name.

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