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

Annotations mark this as not read-only and not idempotent, which would otherwise be confusing for a lookup, and the description supplies the missing context: minimal operational telemetry records no arguments or results. It also discloses the return shape and the boundary that suitability for a child is out of scope. It does not state error behavior for mismatched product/label_band pairs, keeping it below 5.

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 the identifier-sourcing rule, then the return summary. Sentences are dense but every one carries information; the telemetry sentence is slightly awkwardly worded but earns its place as a privacy disclosure.

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 not be exhaustively explained, yet the description still summarizes them usefully. The main remaining gap is failure behavior for incompatible product_id/label_band combinations, which an agent may hit with 12 bands across 5 products.

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% with enums, so the baseline is 3; the description adds real value on top by requiring all three identifiers to be copied from the same bottle and one of its label_bands, which is a cross-parameter consistency constraint the schema cannot express. It does not explain what happens when a band is valid for the enum but not for the chosen product.

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?

"Read one printed public label row" is a specific verb plus resource, and the following sentences spell out exactly what a row yields (amount or ask_doctor, age/weight restrictions, directions, source URL). It is clearly distinguishable from the list_/find_ siblings, which it names as identifier sources.

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?

It states where identifiers must come from (list_calculator_bottles or find_label_references), gives the condition for skipping discovery ("if already known, call directly without repeating discovery"), and adds a scope exclusion ("Does not determine suitability for a child"). When-to-use, how-to-prepare, and when-not are all present.

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