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

Annotations already mark the tool read-only, so the description mainly adds that only active listings are returned and that output is structured for comparison. It does not disclose pagination behavior, default sorting, or language fallback details, though the schema covers some of these. No contradiction with the readOnlyHint annotation.

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?

Three short sentences carry all essential information, and the action verb is front-loaded. There is no filler, repetition of schema details, or tangential content.

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 12-parameter search tool without an output schema, the description is solid but not exhaustive: the schema covers most parameter semantics and annotations cover safety. It adds active-only scope, language range, and a promise of comparable structured fields, but an agent still gets no detailed return shape beyond that. It is adequate for selecting and calling the tool correctly, though not fully self-contained.

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?

With 67% schema description coverage, most parameters are already documented. The description adds real value by defining 'offer' and 'request', which otherwise have no schema descriptions, and by framing search as free text plus filters. The remaining undocumented parameters (limit, offset, category) are low-risk and largely self-explanatory.

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 action ('Search'), a precise resource ('active listings'), a scope ('any of the six languages'), and a method ('free text and filters'). It also disambiguates 'offer' vs 'request', which are core listing kinds. The plural search focus separates it from the sibling get_listing, which is a single-record lookup.

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 implies this is the tool for finding active listings, but it never gives explicit when-to-use or when-not-to-use conditions, nor does it name get_listing as the alternative for fetching a specific listing. An agent has to infer routing from the title and the word 'search.' No exclusions or edge conditions are provided.

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