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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds useful behavioral context beyond annotations: successful jobs return JSON inline or save XLSX/CSV files locally over stdio, while HTTP mode returns safe download instructions. This clarifies surprising mode-dependent behavior without contradicting the annotations.

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?

Two sentences with no filler. The first sentence states the core action, and the second covers result behavior and usage timing. Every clause contributes meaningful information.

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 output schema covers return values, so the description does not need to detail them. It covers the main execution modes and when to call the tool, but it does not describe the polling lifecycle or failure/status behavior in depth. Given the presence of a rich schema and clear annotations, this is still a solidly complete description.

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?

Schema coverage is 100%, so the baseline is 3. The description adds value by linking output delivery to stdio vs HTTP modes, which enriches the meaning of result_type and output_path beyond the schema. It does not restate the parameter details, making it a useful complement.

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 and resource: 'Get the current state of one MainBook conversion.' It distinguishes this from siblings like list_conversions (plural listing) and convert_bank_statement (creation trigger) by focusing on a single conversion's state and result retrieval.

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?

It explicitly tells the agent when to use the tool: 'Use this after convert_bank_statement times out.' This provides clear timing context. It does not explicitly mention alternatives or when not to use it, but the purpose and predecessor relationship are clear enough.

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