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

With no annotations, the description carries full weight. It openly discloses a non-obvious behavior: the denominator includes ALL hours logged, including unbilled time. It could also mention output shape or handling of missing client matches, but the core behavior is well conveyed.

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, front-loaded formula, and no filler. The 'Exposes which clients quietly pay half your rate' line adds practical value without bloat.

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 covers the inputs, the calculation, and the intended decision. Since there is no output schema, it could explicitly state the return format, but the output concept ('real $/hr per client') is already clear.

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 description coverage is 0%, so the description must compensate. It maps 'collected' to 'dollars actually collected' and 'work_entries' to 'ALL hours logged', giving both required parameters real meaning. It doesn't detail the inner object fields, but the schema already exposes client/amount/hours.

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 states a clear calculation: 'dollars actually collected divided by ALL hours logged' per client. It names the resource and purpose precisely and is easily distinguished from sibling finance tools like cash_runway or invoice_aging.

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 gives clear context: freelancers wanting per-client effective hourly rates to identify underpriced clients. It does not explicitly name alternatives or exclusion conditions, so it stops 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.