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. The explicit statement 'Does not move funds' is a critical side-effect disclosure that prevents accidental fund transfers. However, it does not describe the output nature (e.g., approval/denial) or any other side effects, leaving some behavioral gaps. The core non-effect is well covered, so a 4 is appropriate.

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 two concise sentences, leading with the core purpose and then a critical safety note. There is no wasted wording, and the most important information (the scrutiny and non-movement) is front-loaded. This is an exemplary level of conciseness.

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 too brief for a tool with five required parameters and no output schema. It omits the return value (e.g., whether the authorization is granted or denied), any prerequisites like having the mandate document, and does not clarify the 'purpose' field's semantics. An agent lacks critical information to interpret the tool's result and handle errors effectively, making it incomplete.

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 description coverage is 0%, so the description must compensate by explaining the parameters. It does not describe any of the five fields (amount, currency, merchant_id, merchant_country, purpose). The context of a 'proposed agent payment' hints at their role but provides no additional meaning beyond the schema's field names, which is insufficient for a tool with no inline descriptions.

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 uses a specific verb ('Evaluate') and a clear resource ('proposed agent payment against a signed spending mandate'), and explicitly states it does not move funds, which distinguishes it from payment execution tools. Even without siblings, the purpose is precise and unambiguous, leaving no doubt about what the 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 clearly implies the use case: evaluating a payment proposal against a mandate before funds are moved. It does not explicitly state when not to use it or mention alternatives, but the context is strong enough that an agent understands when to invoke it. Since no siblings are present, the lack of exclusions is acceptable.

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