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

Annotations establish it is a non-read-only, non-destructive, non-idempotent write. The description adds genuinely useful context beyond that: an API key is required ('Needs a key'), the listing must pay a reseller share, and there is an ongoing payout effect once the shop_url is shared. It stops short of warning what a repeat call does given idempotentHint=false.

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?

Front-loads the core action and stays to two sentences. The parenthetical '(like a storefront)' and the marketing-ish payout line are slightly loose but not wasteful enough to hurt selection.

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 2-param mutation tool with no output schema, the description covers the auth requirement and the post-call payout mechanic, which is decent. It omits what a call returns, where shop_url comes from, and behavior on duplicate adds despite non-idempotency, so it is only adequately complete.

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%, so the description must carry the load. It implicitly maps both params: 'a product' corresponds to listing_id and 'with a note why you recommend it' describes the note field. However, it gives no format, id type, or length guidance for either parameter, leaving meaningful gaps.

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: 'put a product ... on your shelf' within 'Your own shop on PazAIr'. This is clearly distinguishable from siblings like shop_remove and get_shop. It does not name an alternative tool, but the shop-scoped framing makes the 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?

Usage is implied by the storefront framing and the reseller-share benefit, but the description never says when to use this versus resell, create_listing, or boost_listing. No prerequisites or exclusions are given beyond the incidental 'Needs a key'.

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