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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful context that suggestions come from a fixed storefront search box (a live proxy of the site's autocomplete), but says nothing about rate limits, failure modes, or result freshness. With annotations doing the heavy lifting, a 3 is appropriate.

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?

Two sentences, zero filler, and the routing constraint (partial phrase vs. submitted query) is front-loaded rather than buried. 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?

For a 3-parameter read-only suggest endpoint, the description covers purpose, scope, and the sibling alternative, while annotations cover safety and an output schema covers return values. Nothing essential is missing, though it could briefly note that results are lightweight suggestion entries rather than full catalog records.

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 100%: q, limit (default 10, max 20), and types (allowed values) are all documented in the schema itself. The description only reinforces the 'partial phrase' semantics of q and adds no format or syntax details beyond the schema, so the baseline 3 applies.

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 ('Fetch') and resource ('product, collection, and query suggestions'), with the source ('Rebag's fixed storefront search box') and trigger ('partial phrase') scoped precisely. It explicitly distinguishes itself from the sibling rebag_search, so an agent can route 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?

Gives the selecting condition (use for a partial phrase / autocomplete-style input) and names the alternative with its own condition ('Use rebag_search for a submitted catalog query'). This is an explicit when-to-use / when-to-use-alternative split, matching the strongest calibration example.

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