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 profile is covered. The description adds ordering ('latest first'), aggregation ('counts per change type'), and an important interpretation caveat about co-occurring medicines in results — meaningful context beyond the annotations.

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 scope and content of the result set in a single dense sentence, followed by the safety constraint. The caveat is restated twice ('never use this to recommend a substitute...' and 'Other medicines in the results are not alternatives'), which is mildly redundant but defensible for a clinical safeguard.

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-shape explanation is not required, and annotations cover the read-only profile. The remaining gap is that an agent gets no hint about result volume, defaults, or how to narrow output via limit, which would matter when results are large.

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 0%, so the description must carry parameter meaning. It implies the time window ('in the last days') and lists the five change types (matching the change_types enum), but never mentions the limit parameter, nor defaults (7 days / 50 results), nor the 1–90 and 1–50 bounds.

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 — shortage changes detected over a recent window — and enumerates exactly which change classes are included (new, status_change, return_date_change, delisted, relisted), which implicitly separates it from the snapshot-oriented list_current_shortages. It never names a sibling or explicitly contrasts with it, so it falls short of a 5.

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?

Gives an explicit hard prohibition — 'never use this to recommend a substitute, an alternative or an equivalent medicine, a dosage change or stopping a treatment' — and clarifies that other medicines appearing in results are not alternatives, which is genuine routing/interpretation guidance. It does not say when to use this instead of list_current_shortages or get_availability, so it stops at 4.

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