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

Annotations declare readOnlyHint=true, and the description aligns by describing a read operation ('List'). The description adds valuable behavioral context beyond annotations: it details the inclusion of SYNCED listings with a sync block (source platform, source URL, last check time) and states they can be edited/promoted/closed. This goes beyond the structured annotation and helps the agent understand the response shape, though it doesn't cover pagination or error behavior.

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 concise, two sentences, and front-loaded with the core purpose. The second sentence efficiently covers the important nuance of synced listings without unnecessary detail. Every word serves a function, and the structure is easy to parse.

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 read-only listing tool with complete schema coverage and readOnlyHint, the description is largely complete. It clarifies the scope, includes statuses, and explains sync behavior. However, the status mismatch with the schema (missing 'completed', adding 'pending review') could create minor gaps, and it doesn't explicitly state default behavior when no filter is applied (though 'across all statuses' implies it). Overall, it covers the essential context well.

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 coverage is 100%, so both parameters (limit and status) are described in the schema. However, the description introduces a status ('pending review') that is not present in the schema's enum (which includes draft, active, closed, completed). This mismatch could mislead the agent into filtering with an invalid status. The description adds no explanatory value beyond the schema and even creates potential confusion, so it falls below the baseline of 3.

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 the tool's purpose: listing the authenticated agent's own listings across all statuses. It specifies the resource (listings), the scope (agent's own), and the statuses covered (draft, pending review, active, closed). It also differentiates from sibling search tools by emphasizing 'own' and mentions synced listings as a special case, making its 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?

The description provides clear context for when to use the tool: when you need to see the agent's own listings, including moderation status and synced items. It does not explicitly name alternatives or state 'when not to use,' but the self-referential scope and the mention of 'authenticated agent's own' implicitly distinguish it from broader search tools like search_listings. This is clear context without explicit exclusions.

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