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

Annotations declare readOnlyHint=true, so the safety profile is already covered; the description adds genuinely useful behavior the annotations can't express — the mandatory two-call sequencing and the fact that available_actions is subsumed by accounts. It stops short of noting error behavior or limits on how many actions can be passed at once.

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?

Numbered steps with the mandatory path first and optionals labeled as such — a good, front-loaded shape for a multi-mode router. Minor slack in restating the actions placeholder literally as 'xxxxxx' three times, but nothing is wasted overall.

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; what an agent needs to drive this router (which mode, in what order, with which arguments, and which mode is redundant) is all present. The only omission, `platform`, is a small gap for an otherwise self-sufficient setup tool.

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, and it does for most: all four `request` values are explained, plus the roles of `actions`, `brand_id`, and `workspace_id`. The `platform` parameter is never mentioned anywhere, leaving one of five parameters fully opaque.

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 title-level sentence ('Helper for planning ... data queries') is somewhat generic, but the enumerated steps make concrete what the tool actually returns at each mode: account metadata plus available_actions, per-action request bodies, and brand guidelines. It implicitly positions itself as the prerequisite discovery step ('REQUIRED before querying') relative to query_data/execute_action, though it never names those siblings.

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 protocol with hard requirements: Step 1 'accounts', Step 2 'actions_details' marked REQUIRED before querying, and a caveat that 'available_actions' is redundant because it is already in the accounts response. An agent knows exactly which call to make first and which one to skip.

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