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

With annotations already covering the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true), the description still adds real behavioral value: the returned submission id, the pending state gated on an emailed confirm link, the 48-hour expiry, and the follow-up tool to poll. It does not explain what happens on duplicate submissions despite idempotentHint=false, nor any auth/rate-limit constraints.

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 front-loaded sentences with no filler; the purpose leads and the operational caveats follow. The final sentence is dense and packs return value, state machine, expiry, and next tool into one line, which is efficient if slightly crowded.

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?

No output schema exists, yet the description discloses the return value (submission id) and the full async lifecycle including expiry and the polling tool. Combined with 100% schema coverage for input, an agent has everything needed to submit correctly and handle the result.

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 schema already documents all 8 parameters including lengths, formats, and the makerEmail confirm-link behavior. The description adds no field-level syntax or format detail beyond that, so the baseline 3 applies.

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?

Opens with a specific verb+resource ('Submit a product to Shiplist') and adds a scope qualifier ('on the maker's behalf'). This is clearly separable from the read-only siblings get_listing, search_listings, list_categories, and get_submission_status without opening any schema.

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?

Gives explicit preconditions for calling it ('Only submit what you verified from the product's repo or site, and only with the maker's go-ahead') and routes the agent to get_submission_status for polling. It stops short of stating when NOT to use it or which sibling to prefer for listing lookups, but the context is clear.

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