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

No annotations are provided, so the description carries full burden. It excellently discloses the critical caveat that prices are raw numbers with no confirmed currency unit, explicitly warns against treating price as a specific denomination or comparing values, and even explains the currency_note field structure in results. This is valuable behavioral context beyond what the schema provides.

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 description is front-loaded with purpose and reasonably compact. It packs significant value into a few sentences, with the critical currency caveat getting prominent placement. Slightly redundant with the price_max/price_min parameter descriptions that repeat the currency warning, but overall efficient.

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 annotations and no output schema, the description carries substantial burden and handles it well. For an 8-param discovery tool with pagination and cross-market nuance, it covers the critical behavioral caveats (currency ambiguity), return structure (paginated, currency_note field), and safety profile (read-only). The mix of data-quality disclosure plus result-shape guidance is strong for a complex tool.

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%, so the baseline is 3. The description adds contextual meaning for price parameters (warning currency issues) and references get_regions and list_categories for market/category valid values, which complements the schema. However, most parameter semantics are already well-covered by the input schema descriptions themselves.

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 clearly states 'Search active listings on Defici.com global marketplace' with a specific verb and resource, and distinguishes itself from siblings by noting it returns paginated results and does not include contact details. It's distinct from get_listing (single-item fetch), get_regions, and list_categories.

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?

The description clearly brands this as a read-only discovery tool and notes that contact details are not included, which helps agents know when NOT to use it (e.g., for contacting sellers). However, it doesn't explicitly name sibling alternatives like get_listing for a single result, or explicitly state when to choose it over other tools.

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