get_account_hierarchy

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. Beyond that the description adds almost nothing behavioral: it does not say whether the hierarchy is returned flat or nested, how deep it recurses, or whether large hierarchies are paginated.

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 plus a compact Args block; the core purpose is front-loaded and nothing is redundant. The docstring-style Args line is slightly verbose given only one optional parameter but costs little.

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?

There is no output schema, so the description should explain the return shape of a 'hierarchy tree,' but it does not say whether children are nested, whether grandchildren are included, or what identifiers come back. For a single-parameter read tool this is acceptable but leaves a real gap for an agent planning follow-up calls.

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 coverage is 0%, so the description must carry the parameter explanation, and it does: customer_id is identified as the MCC customer ID, and the fallback behavior ('uses default if not provided') is stated even though the schema only shows default null.

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 specific verb and resource: 'Get the MCC account hierarchy tree,' then clarifies it lists all child accounts under the given MCC account. That distinguishes it reasonably from flat-list siblings like list_accessible_accounts, though it never explicitly names an alternative.

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?

Usage is implied by the MCC scoping ('under the given MCC account'), but there is no explicit when-to-use guidance, no comparison to list_accessible_accounts, and no statement of prerequisites such as which account IDs are valid MCCs.

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