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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered by structured data. The description adds the result shape (ID, unit, typical daily amount, per-serving maximum), but does not say what happens on a partial or zero match — a meaningful omission for a batch lookup.

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?

Three tight sentences, front-loaded with the action and examples, then batching, then return payload. Nothing is repeated and every clause carries information an agent would not get from the schema alone.

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?

For a one-parameter read tool with full annotation coverage and an output schema, the definition covers purpose, batching, and downstream use adequately. The gaps are the no-match/partial-match behavior and the batch size limit, both of which an agent could hit in practice.

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 the meaning of the single `names` parameter. It does convey that these are ingredient names and that multiple may be passed at once, with examples clarifying expected phrasing, but it never mentions the 20-item cap or name length bounds now enforced by the schema — baseline 3 is right.

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?

The description names a specific verb and resource ("look up ingredients ... by name") and anchors it with three concrete examples ("magnesium glycinate", "vitamin D3", "fish oil"). It also distinguishes itself from the only sibling by stating the returned ID is input for draft_supplement_formula, so an agent can place it in the workflow 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?

Usage context is clear: resolve ingredient names before drafting a formula, and batch several names in one call ("Takes several names at once"). There is no explicit when-not-to-use clause or note about what to do when a name is unrecognized, which keeps it below a 5.

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