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

With readOnlyHint=true already covering safety, the description adds meaningful behavior: accounts returns workspace_id, brand_id, account_id and available_actions; actions_details returns the exact request body structure and must precede querying. It does not discuss permissions, rate limits, or other operational constraints, but the annotations and output schema reduce the need for that.

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 tightly structured with numbered steps and optional modes, front-loading the required workflow. Every line maps to a mode or parameter and there is no filler.

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 five-parameter, multi-mode setup helper with an output schema and readOnlyHint annotation, the description covers the essential workflow and return semantics. The missing platform parameter and lack of explicit sibling routing are notable but minor gaps in an otherwise complete definition.

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 carry parameter meaning. It explains the request enum values and the actions input with example action strings, and mentions brand_id + workspace_id for the brands mode, but it omits the platform parameter entirely.

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 function: planning TikTok Ads data queries and retrieving setup metadata such as accounts, available actions, action details, and brand guidelines. It distinguishes itself from downstream querying by noting that Step 2 is REQUIRED before querying, though it does not explicitly name the query_data sibling.

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 usage flow is explicit: Step 1 is request='accounts', Step 2 is request='actions_details' with specific action strings and is marked REQUIRED before querying, and other modes are labeled Optional. It lacks explicit when-not-to-use guidance or named alternatives among siblings.

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