List customer lists

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds genuine value beyond that by explaining that status TOO_SMALL means fewer than 100 matched Pinterest users. It says nothing about pagination behavior, ordering, or what a null ad_account_id implies, so it adds only partial behavioral context.

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 short sentences, front-loaded with the action and resource, with no filler. The status note is compact and earns its place, though the second sentence reads as a fragment and its placement slightly interrupts the flow of the core purpose statement.

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?

An output schema exists, so return values need not be described, and annotations carry the safety profile. However, for a listing tool with two undocumented parameters and no note on pagination or account scoping, an agent lacks enough to call it confidently in multi-account contexts.

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 0% and neither of the two parameters is mentioned in the description. It does not explain that max_results caps the page size (default 200) or that ad_account_id scopes the listing, and the null default — which likely means 'across all accounts' — is left entirely to guesswork.

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 gives a specific verb+resource ("List customer lists") and parenthetically disambiguates the resource as "uploaded customer identifiers", which separates it from the audience tools (list_audiences/get_audience) in the sibling set. It stops short of explicitly naming those siblings, so an agent must still infer the boundary.

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 when-to-use or when-not-to-use guidance, and no mention of the sibling tools (create_customer_list, update_customer_list, list_audiences) that an agent might confuse this with. The only contextual note explains a status value, which is interpretation guidance rather than usage guidance.

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