books_mark_bill_as_paid

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

With no annotations, the description carries the full burden of behavioral disclosure. It fails to mention side effects, reversibility, prerequisites (e.g., whether a payment is required), or any state changes beyond the vague 'mark as paid'.

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 concise with a single sentence and no fluff, but it is under-specified. Conciseness alone does not compensate for the lack of useful detail, so it earns a middle score.

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 simple mutation tool with one parameter and no output schema, the description is too minimal. It doesn't explain the workflow, what 'paid' means in the system, or how it relates to other bill operations.

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 parameter bill_id is not mentioned in the description. Schema coverage is 0%, and the description adds no meaning about the parameter's format, purpose, or constraints beyond the bare 'string' type.

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 'Mark a bill as paid' uses a specific verb and resource, clearly indicating the action. It distinguishes from siblings like books_mark_bill_as_open and books_record_bill_payment, though it doesn't explicitly differentiate the status-change semantics from recording a payment.

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?

No guidance is provided on when to use this tool versus alternatives such as books_record_bill_payment or books_mark_bill_as_open. The agent must infer the appropriate context from the name alone.

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