list_affected_accounts

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description contributes the useful constraint that the call is scoped to exactly one event, but says nothing about result volume, pagination, or what happens with an event ARN from a non-org event.

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 opening sentence is front-loaded and precise. The trailing 'Args:' block merely restates the schema, and the two example prompts are near-duplicates of the same blast-radius question, so the tail adds bulk more 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?

With one parameter, rich annotations and an output schema, the description needn't explain return values, and it successfully conveys purpose, the single-event scope and the ARN's required provenance. The remaining gap is routing: nothing tells the agent when to prefer this over the entity-based siblings.

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 single parameter gets no documentation from the schema alone; the Args block does clarify that event_arn must be an 'organization health event' ARN, which is a meaningful constraint. It still does not say where to obtain that ARN (e.g. get_org_health_events) or what a malformed ARN yields.

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 ('List the organization accounts affected by a single health event') and constrains scope to one event, which separates it from aggregate siblings like count_affected_entities. It never names the closest alternatives (get_affected_entities, get_org_affected_entities), so the agent must infer the accounts-vs-entities distinction.

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 example prompts ('Which accounts does this event affect?') imply the usage context of blast-radius investigation but give no explicit when-to-use/when-not-to-use rules. There is no guidance on how this differs from the entity-oriented siblings, which is the main routing ambiguity an agent faces here.

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