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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description does not contradict that, and its item list is the only hint at what the response contains, but it adds no behavioral detail such as the 400-for-unsupported-year behavior or the 2026-only phase-out scope, both of which live only in the schema.

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?

A single compact clause, front-loaded with the domain and followed by an enumerated scope. Nothing is padded, though the telegraphic style (no verb, colon-separated list) leaves it slightly under-specified rather than optimally crisp.

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?

With no output schema and six optional parameters, the description should at least sketch the return shape (a per-year limits table) and default behavior when called with no arguments. It gestures at the covered categories but never says what comes back or what the defaults produce, leaving real gaps for a zero-required-parameter tool.

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 100%, and the property descriptions are unusually rich — they explain catch-up amounts by age, the magi/filingStatus interaction, and the 2025/2026 taxYear constraint. The description contributes nothing about any of the six parameters, so baseline 3 applies.

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 names a concrete resource set — '401(k), SIMPLE, IRA, Roth phase-out and HSA' contribution limits by tax year — so an agent can tell it is a limits-lookup, not a calculator. However, it is a bare noun phrase with no verb, and it never distinguishes itself from close siblings like converters_401k, converters_retirement, or converters_rmd, all of which sound related.

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?

There is no when-to-use guidance, no exclusions, and no named alternatives. An agent choosing between this and converters_401k or converters_retirement gets no routing signal from the description and must infer the split from the tool name alone.

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