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

The description goes far beyond the annotations by explaining the Emergency Brake's automatic campaign-pausing behavior, the re-arming effect of raising global_budget, and the explicit warning that it writes real configuration that can stop live campaigns. This provides rich behavioral context not present in the readOnlyHint/destructiveHint flags.

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 five sentences, each carrying essential information: the core action, the default brake state, the disarm behavior, the re-arming nuance, and a safety warning. No filler or repetition, and the structure is logical.

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?

Despite lacking an output schema and having minimal annotations, the description covers the tool's key behaviors, side effects, and a critical warning. It addresses the five parameters indirectly through context and provides enough information for an agent to use the tool safely and correctly.

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?

With 100% schema coverage, the baseline is 3, but the description adds meaningful behavioral details for emergency_brake (default armed, consequence of disarming) and global_budget (raising it re-arms a spent brake). These insights go beyond the parameter descriptions in the schema, justifying a higher score.

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 explicitly states the tool's function: setting the account budget amount/period and arming/disarming the Emergency Brake. This clearly distinguishes it from siblings like get_budget and release_brake by naming the specific resources and actions.

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 clear context on when to use the tool, such as the Emergency Brake default state and the effect of passing emergency_brake=false. However, it does not explicitly mention alternatives like release_brake or when not to use this tool, so it lacks exclusionary guidance.

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