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

Annotations already mark this as destructive (destructiveHint=true). The description adds valuable behavior context: it requires a card to be set, warns that submission fails without extra info, and instructs not to guess refresh_token. It does not contradict annotations and supplements them with practical failure conditions.

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 reasonably concise and front-loaded with the primary purpose, followed by critical prerequisites and constraints. Some redundancy (e.g., 'do not call this until you have asked' repeated in the user_amount_statement explanation) could be trimmed, but overall it is efficiently structured.

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?

Given the tool's complexity (nested object, output schema present), the description covers prerequisites (card set, user confirmation), failure conditions (extra_infos), and special field handling (entered_account/entered_provider, refresh_token). It omits details about return values, but an output schema exists, so this is acceptable.

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 provides rich descriptions for all parameters (e.g., user_amount_statement, refresh_token, entered_account), so the baseline is 3. The tool description only gives a high-level summary of confirm_input ('identifiers, the amount to pay, contact info and any extra info') without adding new parameter-level meaning, thus meeting but not exceeding the baseline.

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 clearly states 'Final step: submit the bill for payment' with a specific verb (submit) and resource (bill), and distinguishes it from siblings by framing it as the final step after bill analysis (referencing analyze_bill). This makes the tool's purpose unambiguous.

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 explicit conditions for use: 'do not call this until you have asked' about the amount, 'If analyze_bill reported a need for extra information, supply it in extra_infos or submission will fail', and guidance to use correction fields only for mis-extracted values. This clear when-to-use and when-not-to-use guidance exceeds the baseline.

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