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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, covering the safety profile. The description adds genuinely useful context not in the annotations — that only merchants with published feedback are returned and that an empty result set does not imply poor quality — but it says nothing about result format, matching behavior, or limits.

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 short sentences with the purpose front-loaded and no filler. The caveat sentence is brief and earns its place by warning about result interpretation, though it is terse enough to feel slightly cryptic.

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 search tool with one undocumented parameter and no output schema, the description should at least explain what 'q' searches and what a result contains. It leaves both open, and the empty-results caveat only partially compensates for the missing parameter semantics.

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?

The single parameter 'q' has 0% schema description coverage and the description never mentions it, so an agent gets no information on what 'q' matches (merchant name, location, category?) or whether it is a free-text query. This is a clear gap for the only parameter.

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 states a verb and resource ('Find merchants') but the qualifier 'with published feedback' is ambiguous — it is unclear whether this is a hard filter (only merchants that have feedback) or merely a scope note. It does not distinguish itself from siblings like find_offerings or get_reputation, which an agent would need to disambiguate the resource being searched.

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?

There is no statement of when to use this tool versus find_offerings, get_reputation, or the other siblings. The second sentence ('Empty results are not evidence of quality') is a caution about interpreting output, not usage guidance, and no prerequisites or alternatives are named.

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