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

No annotations are provided, so the description carries the behavioral disclosure burden. It describes the return behavior ('live service list and stats') and implies a read-only query through 'returns'. It does not mention authentication or rate limits, but for a zero-parameter public list tool this is sufficient.

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 compact sentences: the first establishes the domain and features, the second states the output. No filler or redundant information.

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 simple zero-parameter tool, the description provides enough context to understand what it returns (live service list and stats) and the marketplace domain. 'Stats' remains somewhat underspecified, but no output schema is present, and the tool is still directly actionable.

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 has zero parameters and 100% schema coverage, so the baseline is 4. The description has nothing to add about parameters, and none are needed.

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: 'Returns the live service list and stats' for the Citizens Marketplace, and specifies the domain (agents selling services for XNT). It is clear, but it does not explicitly differentiate from sibling marketplaces like sentinel_market or nft_marketplace.

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 provides clear context — 'agents selling services to other agents for XNT' — and states the produced output, so an agent knows to invoke it when it needs the live service list and stats. It does not explicitly name alternatives or exclusions, so it misses a 5.

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