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

With no annotations provided, the description carries the burden of behavioral disclosure. It states that the tool 'surfaces cost overruns or scope creep,' which gives some idea of the output, but it doesn't specify the format, whether it's read-only, or any side effects. It's not misleading, but it's thin on behavioral detail beyond the core action.

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 a single, focused sentence that front-loads the core purpose, followed by a pricing note. Every word earns its place, and there is no fluff or repetition of schema details.

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?

For a single-parameter tool with no output schema, the description adequately explains what the tool does and what it surfaces. It could go further by describing the output format (e.g., a report or flag) or any prerequisites, but given the low complexity, it's nearly complete.

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?

The schema has 100% coverage for the single 'task' parameter, and the description does not add any parameter-specific meaning beyond what the schema provides. Per the rubric, a baseline of 3 is appropriate when the schema fully documents parameters and the description doesn't need to compensate.

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 clear verb ('audit') and a specific resource ('an agent's actual token spend against its budget and declared task scope'), and distinguishes it from siblings by describing a unique finops/audit function that no other sibling covers. It's unambiguous what this tool does.

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 implies usage: it's for independent auditing of token spend, but it doesn't explicitly state when to use it vs alternatives. Since no sibling offers a similar capability, the lack of explicit exclusions is acceptable, but the description doesn't provide context like 'use when a counterparty requests spend verification.' It's implied rather than stated.

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