get_dac_ur

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

With no annotations available, the description carries the transparency burden. The verb 'View' clearly indicates a read-only operation, and the description mentions the breakdown content. However, it does not explicitly state that the tool performs no mutations, nor does it disclose any required permissions or side effects, leaving room for more clarity.

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 two sentences that immediately state the tool's purpose and use case. It front-loads the key information and avoids fluff or redundancy. Every sentence earns its place.

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 read-only report tool with a simple parameter set, the description is complete enough. It explains what the report contains and why it is useful. The absence of an output schema is mitigated by the description's explicit mention of 'detailed breakdown by service, period, and transaction type.' It could have mentioned required auth explicitly, but the schema covers that, so overall this is well-rounded.

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 input schema already provides 100% description coverage for all three parameters (to, from, auth_token), so the baseline is 3. The description adds no extra semantic detail beyond alluding to a 'period' via the date parameters, but since the schema is thorough, this is sufficient.

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 the tool's function: 'View your DAC usage report — a detailed breakdown of spending by service, period, and transaction type.' It uses a specific verb ('View') with a specific resource ('DAC usage report') and distinguishes it from related tools like get_dac_balance by emphasizing the detailed breakdown and spending analysis.

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 clear context for when to use this tool: 'Useful for budgeting and trajectory analysis.' It implies this is the go-to tool for viewing spending reports but does not explicitly mention alternative tools or exclusion criteria, so it falls short of a 5.

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