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

With no annotations, the description carries full responsibility for explaining behavior. It does not describe what the tool does, its effects, or any side conditions (e.g., whether it reads, writes, or updates). The mention of 'Paid $0.01 USDC Base x402' is cryptic and unexplained, offering no transparency about actual behavior.

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 extremely brief but poorly structured. It is a fragmentary set of phrases without logical flow or clear subject-verb-object construction. The inclusion of seemingly random elements ('Optional number', 'Paid $0.01 USDC Base x402') makes it disjointed and hard to parse.

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?

The description is severely incomplete. It does not explain the tool's role in the broader system, what inputs or outputs to expect, or any relevant context such as what 'CGI 289' refers to. Even the basic purpose is not fully clarified, leaving an agent without enough information to use the tool 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?

The tool has zero parameters, so schema coverage is effectively 100%. According to the baseline rule, a score of 3 is appropriate even without additional parameter information. The description does not need to explain parameters because there are none.

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 it is a 'French pro forma header' and notes it is not an invoice (CGI 289), but it lacks a specific action verb or clear indication of what the tool does. The phrases 'Optional number' and 'Paid $0.01 USDC Base x402' add confusion rather than clarity, making the purpose ambiguous.

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 guidance on when to use this tool versus alternatives. The sibling list contains many related tools, but the description does not mention any conditions, dependencies, or reasons to choose this tool over others.

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