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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the bar is lower; the description adds genuinely useful behavior beyond them: prefix-only matching semantics with a worked counterexample ("DOLIPRANE" vs "CODOLIPRANE") and the intersection behavior when both name and substance are supplied. It does not state pagination or result ordering, which is a minor gap.

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-loads the core purpose, then packs matching semantics, examples, and the downstream handoff into compact sentences without filler. Slightly dense with three parentheticals, but every clause earns its place.

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, the description compensates by naming the returned fields (CIS code, denomination, holder, pharmaceutical form, marketing status). Matching semantics and the downstream fr_medicine workflow are covered; only ordering/pagination of results is omitted.

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 baseline is 3; the description goes beyond the schema by explaining the prefix-only matching rule for both name and substance and how the two filters combine (intersection). The limit parameter remains undocumented beyond the schema's own 1-100/default note.

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 (search) plus resource (French medicines in BDPM) and the match key (name prefix and/or active substance), and enumerates returned fields. It is clearly distinguishable from siblings like fr_medicine (which takes a CIS code) and fr_generic_group.

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 concrete when-to-use examples ("medicines containing paracetamol", "search Doliprane") and explicitly routes the agent onward by noting the CIS code is meant to be passed to fr_medicine. It stops short of stating exclusions versus fr_generic_group, but the primary workflow is unambiguous.

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