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

Annotations only cover read-only and open-world nature, but the description discloses non-obvious upstream behavior: an unrecognized category is silently ignored (returning the unfiltered catalog, not zero results or an error), a zero-match query returns a well-formed empty result, and product_type is a closed 14-value enum. These are exactly the traps an agent needs to know about.

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?

Dense but every sentence carries weight, and the purpose leads. It is on the longer side with several parenthetical asides, but none are filler given the parameter complexity.

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 an output schema present, return values need no explanation, and the description covers all 8 optional parameters, their sourcing, AND-combination, and edge-case behavior. Nothing an agent needs to invoke this correctly is missing.

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 already 100%, but the description adds cross-parameter dependency semantics the schema only hints at: category+product_type must come from the same reverb_categories entry because the slug is not globally unique, and make is called out as a confirmed real filter. The silent-ignore caveat for category adds further meaning beyond the schema.

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/browse) and resource (Reverb's marketplace for new and used musical instruments and gear) and names the field surface. It also implicitly distinguishes itself from siblings reverb_categories and reverb_makes by positioning them as sources of valid filter values rather than competing searches.

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 clear routing guidance: category values must be drawn from reverb_categories' categories[].slug, product_type must be passed with category from the SAME entry, and make comes from reverb_makes' makes[]. It does not explicitly state when to prefer reverb_price_guide or reverb_listing instead, so it stops short of a full when/when-not matrix.

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