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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, yet the description still adds real behavioral context: OAuth store:read consent, an approved-store ownership prerequisite, a specific error when no approved store exists, an empty page for no matches, and an error on malformed cursors. It also enumerates the returned row fields and pagination metadata in the absence of an output schema.

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-loaded with purpose, then scope, then returns, then auth/error behavior — a sensible ordering with no filler sentences. It runs long and includes a clause ('Read-only; no repricing, stock reservation or publication') that partially restates the readOnlyHint annotation, costing a small amount of redundancy.

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 filtered, paginated read with no output schema, the description covers everything an agent needs: scope, ordering, pagination continuation rules, returned fields, auth consent, store prerequisite, and both empty-result and cursor-error outcomes. Nothing material is left to inference.

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 limit, cursor and the status enum are already fully documented in the schema. The description only restates the cursor semantics ('nextCursor continues with the same status filter and limit'), adding reinforcement rather than new meaning. Baseline 3 applies when the schema carries the parameter burden.

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 ('List individual listings owned by the connected seller's store, newest first') and bounds the scope by excluding aggregate stock counts, customer purchases and changing listings, which implicitly routes the agent away from get_store_inventory and sales-activity siblings. An agent can distinguish this listing-level read from the other store tools without opening a 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?

Explicitly says when to use it ('Use to inspect listing-level prices, quantities or status') and when not to (aggregate stock counts, purchases, changing listings are outside this read). It also explains that nextCursor keeps the same status filter and limit. The only gap is that it never names a concrete alternative sibling tool such as search_listings or get_listing by name.

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