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

With no annotations, the description carries the full burden and does so thoroughly. It discloses that data is cached and can be stale, that the server re-verifies advertiser linkage before approval, that cursors can become rejected or old, that pagination must be followed serially until complete=true, and that 'complete' only refers to pagination, not sync coverage or permissions.

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 dense but front-loaded with the core purpose, then usage, pagination rules, prerequisites, and an example. Every clause adds practical value, including the clarification about 'complete' meaning only pagination, so no sentence is wasted.

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?

Despite having no annotations and no output schema, the description covers the tool's purpose, required inputs, parameter behavior, pagination protocol, staleness handling, prerequisite data source, and downstream usage. It is complete enough for an agent to select and call the tool correctly.

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%, so the description must compensate, and it does. It explains advertiser_id is required and sourced from a sibling tool, adds the limit maximum of 50, describes cursor continuation and restart semantics, and clarifies search as case-insensitive native id/name lookup. The example further anchors parameter usage.

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 begins with a specific verb and resource: 'List cached TikTok CTA portfolios for one exact advertiser.' It is clearly distinguishable from sibling assets_list_* tools by the CTA-portfolio resource and the cached/exact-advertiser scoping, and it explains how the output is used (as creative_portfolio_id / call_to_action_id).

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 gives clear context: when the list is empty or stale, refresh assets first; never guess a portfolio ID; advertiser_id must come from assets_list_ad_accounts; keep the same tool and filters during pagination. It does not explicitly name an alternative sibling to use instead, so it stops just short of full alternative-routing guidance.

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