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

With no annotations provided, the description carries full responsibility for disclosing behavior. It mentions the comparison and the break-even, but does not disclose assumptions, limitations, default handling, or whether the tool is read-only. The agent is left without information about edge cases or input constraints.

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 two sentences, front-loads the core purpose, and every clause adds value. It avoids redundancy and is highly efficient.

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 calculator tool with no annotations and no output schema, the description gives the essential purpose but does not describe the return format or any caveats. It is adequate for a basic planning tool but lacks the depth needed to fully anticipate results, especially since the output schema is absent.

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% coverage for all three parameters (revenue, type, operating_itcs), so the description adds marginal value. It does note 'Ontario contractor' and 'break-even' but does not elaborate on parameter meaning beyond the schema's own descriptions.

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 compares the CRA Quick Method against the regular method for an Ontario contractor, specifying the outputs (remit, keep, break-even). This distinguishes it from sibling tools like required_hourly_rate or estimate_contractor_tax, which address different tax calculations.

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 phrasing 'Planning estimate' implies use for planning/estimation, but there is no explicit guidance on when to use this tool versus sibling tools, nor any exclusions or prerequisites. The context is loosely implied but not clearly defined.

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