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

Consistent with readOnlyHint=true — every branch is a retrieval. The description adds real behavioral context beyond the annotations: it discloses what each branch returns (workspace_id, brand_id, ad_account_id, available_actions, exact request body and notes) and flags a mandatory ordering dependency. It does not mention rate limits or error behavior, but the key operational traits are present.

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?

Front-loaded with the two required steps, then optional branches, which matches execution order and is easy to scan. Minor redundancy in explaining available_actions as already included in the accounts response, and the placeholder array 'xxxxxx' repeated three times is noise rather than information.

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 shapes need not be spelled out, and the description still summarizes them usefully. For a five-parameter, four-branch orchestration tool the workflow coverage is good; the unaddressed platform parameter and the absent cross-reference to execute_action/query_data are the remaining gaps.

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 carries the burden and covers four of five parameters well: all four request enum values are explained, the actions array's content source is stated, and brand_id/workspace_id pairing for the brands branch is specified. The platform parameter is never mentioned anywhere, leaving one gap.

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 concrete verb and resource: a helper that plans Snapchat Ads data queries and returns setup metadata plus action request bodies. The step-by-step framing makes the tool's role clear, but it never says how it relates to the siblings execute_action or query_data, so an agent must infer that this is the prerequisite discovery step rather than the actual query tool.

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?

Gives an explicit ordered workflow: request='accounts' first, then request='actions_details' which is called out as REQUIRED before querying, plus optional calls for available_actions and brands. The 'when' is clear and there is an implied exclusion (don't query without actions_details), but no direct routing to the sibling tools that would consume this output.

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