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

Annotations only declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false). The description adds substantial behavioral context beyond them: proposals are simulated first, nothing is sent until the seller approves, and the marketplace reviews each product before it goes on sale. It also discloses platform quirks (Temu base price, category_id 0 auto-selection, vat_rate ignored).

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?

Dense but front-loaded: the blocking-prerequisite warning leads, then the purpose, then platform-specific and variant rules. Nearly every clause earns its place, though the purpose sentence ('Propose new products') is buried mid-paragraph and could be surfaced first.

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 mutation tool with an output schema already documenting returns, the description covers the gaps that matter: the required pre-write workflow, the simulate-then-approve-then-review lifecycle, variant modeling via shared product_main_id, and per-marketplace parameter overrides. An agent has enough to invoke it correctly.

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 50%, so the description usefully compensates: it defines Temu's price-as-base-price semantics, category_id 0 auto-selection, vat_rate being ignored, the required dimensions on Temu, and how product_main_id groups variants. It adds meaning beyond the schema for several fields but leaves other platform-specific parameters to the schema.

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 ('Propose new products') and implicitly distinguishes from the offers_update_* siblings, which mutate existing offers. It also frames the tool as a 'catalog change' subject to guide/check prerequisites, so an agent knows this is the create path.

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 an explicit prerequisite workflow: call listing_guide before writing titles/descriptions/pictures/attributes and validate the draft with listing_check, since a blocking finding is refused here. It also points to categories_get for required attributes. It stops short of naming the sibling alternatives (offers_update_price, offers_update_content) for modifying existing offers.

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