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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds substantial behavioral detail beyond that: stock checking and basket-id resolution order, 'bskState del/limit describes UI buttons, not availability', demoScope restrictions, session reuse without SMS upgrades, and the explicit statement 'This does not create an order or pay.' This is rich, non-redundant context that helps the agent avoid harmful or confusing actions.

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 front-loaded with the purpose, but it is a long single paragraph with many imperative constraints. Several rules such as 'Never web-search', 'Never ask the owner to edit connector settings or reconnect', and 'Never brute-force ids' are useful but could be more tightly grouped or trimmed. It earns its place for complexity, but the lack of structure hurts readability.

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 complex tool with no output schema, the description covers a lot: what the tool does, session recovery, demoScope constraints, payment disclaimer, and troubleshooting guidance. It mentions 'Preserve resolvedItems and quantities' and 'share openUrl only if returned', giving hints about the return payload. It is not fully exhaustive about failure modes or exact return format, but it provides enough for an agent 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 88%, so the schema already documents most parameters. The description adds meaningful semantic guidance on top: 'Pass item queries plus optional preferred external catalog ids' maps directly to the items array, and the sessionId handling ('pass sessionId and retry', 'Never invent a sessionId') clarifies the schema's brief description. It also clarifies that id is not for brute-forcing, which is valuable.

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 states a specific verb and resource: 'Dixy-only live basket resolver' that 'searches the selected shop's official JSON catalog, checks stock and resolves internal basket ids before adding.' This clearly differentiates it from sibling purchase, payment, and Ozerki tools, and from generic cart tools like prepare_dixy_checkout.

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 gives strong usage context: it is Dixy-only, should not be used to create orders or pay, and provides explicit actions for session recovery ('Recover dixySessionId through start_dixy_call_auth'). It also gives clear when-not-to instructions ('Never brute-force ids with cart mutations', 'Never begin_agent_link again'). It does not explicitly name alternative sibling tools for comparison, but the boundaries are clear.

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