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

Annotations already declare readOnly, idempotent, closed-world, non-destructive, so restating 'read-only, no network, no stored state, deterministic' earns little new credit. What does add value beyond the structured fields is the operational envelope: 64 KB JSON input, 1 s per call, 1 MB result, and 12 significant digits of precision. That is genuine disclosure, just partly offset by redundant safety restatement.

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 conversion statement, then cleanly labeled sections (When / Not for / Side effects / Deterministic / Limits). The one cost is that the entire content is duplicated in Spanish and English, roughly doubling length for an agent that only needs one.

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 tool is simple (3 scalar params, no nesting), an output schema exists so return shape need not be explained, and the description covers units, defaults, precision, exclusions, and resource limits. Nothing an agent needs to call this correctly is missing.

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 is 3; the description still adds meaning by clarifying that omitting 'to' returns all units and that output carries 12 significant digits. It also supplies the full unit vocabulary that the schema only gives for 'from', which reduces the risk of an invalid 'to' value.

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?

Names a specific verb and resource (converts flow rate between units) and enumerates the exact supported units (m3/s, m3/h, l/s, l/min, l/h, gal/min, ft3/min). It explicitly distinguishes itself from the nearest sibling, convert-volume, so an agent can route without inspecting 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?

Provides an explicit 'When' clause (converting a quantity between units with exact definitional factors) and an explicit 'Not for' clause naming the alternative tool convert-volume. It also states the default behavior when 'to' is omitted, so the omission case is unambiguous.

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