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

With no annotations, the description carries the full load and does disclose key traits: it is a read-only style lookup ('See'), it is 'Free' (cost), and it requires auth credentials from marketplace_register. It stops short of describing return shape or pagination, but the essential behavioral facts are present.

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?

Four short clauses, front-loaded with the seller/buyer disambiguation, then purpose, then cost, then auth. No filler sentences.

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 two-parameter read tool with no output schema, the description covers purpose, role distinction, cost, and credential sourcing. The only gap is that it does not indicate what the returned listing/price data looks like.

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 0% for the two required parameters, so the description must compensate. It names both (agent_id, api_key) and helpfully notes the api_key's provenance ('from marketplace_register'), but adds no format or syntax detail beyond that.

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 and resource ('See the services you offer and their prices') and immediately scopes it as the seller path, which cleanly separates it from buyer-path siblings and the broader marketplace_services browse tool.

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?

Explicitly frames when this applies ('Seller path -- not a buyer step') and gives a concrete use case ('to confirm a listing is live'). It does not name the alternative tool (e.g., marketplace_services) by name, but the buyer/seller framing is sufficient context.

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