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

Annotations provide readOnlyHint=false, destructiveHint=false, but no contradiction. The description claims it is a write operation and mentions bulk support, but it does not disclose behavioral details like whether the simulation modifies state or just previews. Given that it's a 'simulate' action, it likely does not make changes, but the description does not state this, and annotations don't clarify. Since annotations are sparse, the description should carry more weight; it fails to explain the effect of the operation.

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 description is poorly structured: it starts with a long list of actions that are not relevant to this specific tool, then adds a clarifying note in brackets. This wastes space and confuses the agent. The bulk support mention is useful but should be placed after a clear purpose statement. It is not front-loaded with the specific action's purpose.

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?

Given the tool's complexity (multiple actions, nested objects, 4 parameters with 0% schema coverage, no output schema), the description is severely incomplete. It does not explain what 'simulate_plan' does, what the expected 'data' structure is, or any return values. The bulk support note is the only extra context. For an agent to correctly invoke this tool, it needs much more detail.

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 explain parameters. The description mentions actions with parameters like '(id, +data opcional)' but does not explain what 'data' contains for simulate_plan. The schema shows an 'id', 'ids', 'data', and 'account' properties but no descriptions. The description provides minimal semantic value beyond the schema property names, failing to compensate for the low coverage.

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 description is a list of many subscription mutation actions but then says '[Flattened action: simulate_plan]', indicating that the tool is for the 'simulate_plan' action only. The purpose is unclear because the description begins by listing many actions, making it hard to distinguish what this specific tool does. It does not clearly state that it simulates a plan change on a subscription; instead, it enumerates all possible mutations, then partially clarifies with the flattened action note.

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 description provides no guidance on when to use this tool vs alternatives. It mentions bulk support but does not explain how to choose between the many subscription write tools (e.g., guru_subscriptions_write_change_plan vs simulate_plan). There is no context about prerequisites or scenarios where simulation is appropriate.

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