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

No annotations are provided, so the description carries the full burden. It discloses the tool computes growth, tax drag, and gives a recommendation, and uses latest contribution limits. However, it doesn't disclose behavior like whether it accounts for employer match, whether recommendation is based on assumptions, how tax drag is modeled, or what happens with different tax rates. For a financial comparison tool with no annotations, more behavioral disclosure is needed.

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 key information: what is compared, time horizon, outputs, and a note on using latest limits. Efficient and front-loaded with the main purpose. Could be slightly more structured but very concise.

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 6-parameter calculator with no output schema and no annotations, the description provides core purpose and outputs but misses notable context: how employer match is used (if at all), whether 401(k) and Roth IRA limits differ by year, what 'recommendation' means, and how tax rates interact. It's adequate for a basic calculator but has gaps for an agent to know edge cases.

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 schema already documents all parameters. The description adds context about the comparison scope (pre-tax vs post-tax, tax drag, contribution limits) that helps parameter intent. It doesn't add detail on specific parameters like years or annualReturn, but with full schema coverage baseline 3 is exceeded slightly by framing contribution and tax rates in the retirement comparison context.

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 401(k) pre-tax vs Roth IRA post-tax, with a specific resource and focus (30-year growth, tax drag, recommendation). It's specific, but doesn't explicitly differentiate from siblings like compare_w2_vs_1099 or compare_llc_cost; however the resource is clear enough.

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 implies usage for retirement account comparison and mentions using latest CDN contribution limitsholidays. It doesn't explicitly state when to use this versus alternatives (like compare_compound_interest for generic growth, or other tax calculators). Context is implied but no exclusions or explicit alternative routing.

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