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

Annotations already declare readOnly=false, destructive=false, openWorld=true. The description adds genuinely new behavior: the risk gate where sizingValue above 10 requires confirmHighRisk "after the user confirms," and a mandatory user-confirmation step before saving. It does not explain what happens to existing members on an update, which is the remaining gap.

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 purpose, then sizing semantics, then the confirmation requirement. Dense but every sentence carries operational information; the parenthetical about percentage risk is essential rather than padding.

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?

With no output schema, the description does the work of explaining the upsert behavior, sizing model, and the high-risk confirmation flow — enough for an agent to call it correctly. Minor omissions remain (update/replace semantics for existing members, error cases), but nothing blocking.

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 100% for the top-level params, but the nested sizing fields carry no schema descriptions, and the description fills that gap precisely: sizingMode enum meanings, sizingValue as "% of the balance LOST if the stop is hit, typically 0.25-2," and the confirmHighRisk threshold. Only brokerAccountId sourcing is left unexplained.

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+resource ("Create or update ... a group of 2+ broker accounts") and pins down the upsert key ("by name"). It also names the downstream consumer (execute_trade_multi) and implicitly separates itself from get_account_groups and delete_account_group.

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?

Clear context for when to use it: grouping 2+ broker accounts to trade together, available on all plans, with an explicit precondition ("Confirm the accounts and sizes with the user before saving"). It does not explicitly name the read/delete siblings as alternatives, so no exclusions are stated.

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