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

With no annotations, the description carries the full burden. It does disclose real behavioral context: the tool is paid ($0.05 USDC on Base via x402), which is essential before calling it, and that output is a diff against the last snapshot. However it omits auth requirements, whether payment is per-call, and what happens if no prior snapshot exists.

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?

A single dense sentence with no filler, and the cost banner is front-loaded so an agent sees the payment requirement first. Slightly compressed, but every clause earns its place.

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 one-parameter, no-output-schema tool the description is nearly sufficient: it covers cost, output shape, and the snapshot dependency. The main gap is the absence of any prerequisite or error behavior when no snapshot exists.

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?

One parameter with 100% schema description coverage, so the schema already documents 'store' with a domain example. The description adds no additional meaning about the parameter, which matches the baseline of 3 when the schema does the work.

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: returns change intelligence versus the last snapshot, and enumerates the diff types (new/removed, price changes, stock changes). This clearly separates it from shopify_snapshot, though 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?

Usage is implied by 'vs the last snapshot' (a prior snapshot must exist) but never stated as a condition, and there is no guidance on when to pick this over shopify_intel_report or shopify_landscape. The paid-cost note is disclosed but is not usage guidance.

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