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

Beyond the readOnlyHint annotation, the description reveals critical behavioral traits: hierarchical subtree matching for category and location, the keyword-based (not semantic) nature of q, and the no-pagination limitation ('Only the first few best matches are returned'). This adds substantial context that annotations alone do not cover.

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?

The three-paragraph structure front-loads the core function and follows with behavioral details and limitations. It's dense but every sentence adds value; slightly long, though justified given the tool's idiosyncrasies.

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?

Given no output schema, the description could detail return values but instead smartly explains the key limitation (no pagination) and recovery strategy. It covers parameter behavior, hierarchies, and edge cases. Not describing the result fields is a minor gap that can be inferred from search results.

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?

Even though schema coverage is 100%, the description goes far beyond: it clarifies that categoryId/locationId match subtrees, explains that q matches across titles/descriptions/attribute values with title/description ranking highest, and warns that synonyms won't match. These are semantic details missing from 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?

The description opens with a specific verb and resource: 'Search published listings by free text, category and location,' clearly stating the tool's function. It doesn't explicitly name sibling tools for differentiation, but the clear scope and the mention of companion tools for ids make the purpose unambiguous.

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 states when to use filters ('Filter at the broadest level the user actually meant'), explains parameter trade-offs ('Prefer q for what an item is, and the id filters for where it is'), and points to companion tools ('Get ids from get_categories and search_locations'). This is explicit when/when-not guidance that an agent can act on directly.

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