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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety repetition is somewhat redundant. However, the description adds genuinely new behavioral context: determinism, no stored state, and hard limits (64 KB JSON input, 1 s per call, 1 MB result) that the annotations do not express.

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?

Front-loaded with the core action, then cleanly labeled sections (When / Not for / Side effects / Deterministic / Limits). The full Spanish-plus-English duplication doubles the length for the same information, which is the main cost, but each version is individually tight and scannable.

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?

An output schema exists, so return values need no explanation, and the description still summarizes it returns the result plus common bases. Combined with limits, determinism, and the explicit sibling exclusion, an agent has everything needed to select and call it correctly.

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 baseline would be 3, but the description adds parsing semantics the schema never states: accepted 0x/0o/0b prefixes, underscore separators, and an optional sign. Those details directly affect how the value parameter must be formatted.

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?

States a specific verb and resource with precise scope: converts an integer of any size between bases 2-36, accepting 0x/0o/0b prefixes. It also explicitly excludes roman-numeral conversion, so an agent can separate it from the most confusable sibling without opening either schema.

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?

Has explicit "When:" (a numeric result must be exact/reproducible, not estimated) and "Not for:" naming the alternative tool (roman-numeral) with the exact range 1-3999 where that sibling applies. Nothing is left to inference.

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