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

With no annotations, the description carries the full behavioral burden. It discloses the cost (0.002 USDC) and budget scopes, but says nothing about what happens when a budget is exceeded, whether the operation blocks or logs, required permissions, idempotency, or side effects.

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 single sentence is front-loaded with the core action and scope, with zero wasted words. It is appropriately sized but extremely terse, bordering on under-specification rather than being structurally deficient.

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 having an output schema, the definition is incomplete for a guard tool with no annotations: it omits critical when-to-use context, behavioral outcomes on enforcement, and any differentiation from siblings. An agent has enough to know the broad purpose but not enough to call it correctly in context.

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 description coverage is reported at 100%, so the structured schema is expected to document parameters, setting the baseline at 3. The description adds no mapping or meaning for the required request, usage, and policy parameters beyond the general budget categories already implied.

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 states a specific verb ('Enforce') and resource ('budgets'), and enumerates per-call, task, session and period scopes, making the core purpose clear. However, it does not differentiate itself from similar sibling guards like subscription_spend_guard or mandate_reserve, so it falls short of a 5.

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?

There is no explicit guidance on when to use this tool versus alternatives, nor any stated exclusions or prerequisites. The budget enforcement context implies a use case, but an agent must infer when to call it relative to the many other guard and payment tools.

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