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

Annotations already declare the tool read-only, idempotent, and non-destructive. The description adds valuable context about what the profile contains and frames the tool's purpose, going beyond what annotations encode. No contradiction with annotations.

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 with no filler. The first sentence packs the resource and returned fields compactly; the second adds the use-case question. The key identifying information is front-loaded.

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 one fully-documented parameter, rich annotations covering safety, and a description that lists output fields and the source context (reverb_search), the agent has everything needed to call the tool correctly. No output schema is needed since the field list is already in the description.

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 input schema fully documents shop_slug with an example and a cross-reference to reverb_search; the description adds no additional parameter semantics beyond that. At 100% schema description coverage, a baseline 3 is appropriate.

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 opens with 'Reverb.com seller profile by shop slug' and enumerates the specific fields returned (shop name, location, feedback count and rating, preferred-seller status, return policy, shipping posture). The second sentence frames it as answering 'who is this seller and what is their track record,' clearly distinguishing it from sibling tools like reverb_search and reverb_listing.

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?

It explicitly ties usage to a prior reverb_search: 'for a listing found via reverb_search.' This gives the agent a clear trigger condition. It doesn't enumerate exclusions (e.g., when to prefer reverb_listing over this tool), so it lacks explicit alternatives, but the context is unambiguous.

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