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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=true), so the description's job is to add context — and it does: the call is free, sign-in is required, and two output fields are interpreted (search.store_endpoint controls whether the shop's native search runs; site_reachable=false means the domain does not resolve). It does not mention rate limits or response timing, but the auth and cost disclosures are substantive.

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?

Capability and cost are front-loaded, and each subsequent sentence is a conditional edge case (store endpoint present/absent, unreachable domain) plus two cost/auth facts. The telegraphic fragments ('Free. Needs sign-in.') are efficient but make the structure feel compressed rather than flowing.

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?

With only two parameters, no output schema, and light annotations, the description carries the return-value burden well by explaining the two fields an agent must act on, plus cost and auth. It omits the overall response shape and does not tie the country parameter to the name-vs-domain behavior, which is a minor gap.

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 both parameters (site, country) are already documented in the schema, including the market-selection role of country. The description adds nothing about either parameter, so 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?

The opening sentence states a specific purpose: reporting what datawebot can do on a shop (search, product details, catalogue) and the credit ceiling per action, as a pre-flight probe. The 'before running anything' clause implicitly distinguishes it from execution siblings like run_tool or search_products, but it never names a sibling explicitly.

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?

'...before running anything' gives a clear usage cue: call this first to scope cost and capability. It stops short of explicit when-not-to-use guidance or naming which sibling to call next (discover, find_endpoints, search_products), leaving the routing inference to the agent.

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