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

With no annotations, the description carries the behavioral burden and does add genuinely useful context: the tool is paid ($0.01 USDC on Base via x402), and the schema's payment_signature note describes the two-call handshake. However, it omits feed-size limits (maxItems 100), what happens when snapshots exceed that, and how records are matched between before/after.

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?

Two sentences, zero filler, with the core operation front-loaded and the cost disclosed immediately after. Nothing in the text is redundant.

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?

No output schema and no annotations, so the description should do more than it does for a 3-param tool. It covers purpose and price adequately but leaves record-matching semantics, the 100-item cap, and large-feed behavior entirely to the schema.

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 only 33% — the two required arrays have no described item shape (additionalProperties true) and no stated matching key. The description's phrase 'changed commerce fields' hints at diff semantics but does not explain what counts as a commerce field or how before/after entries correspond, so it fails to compensate for the undocumented parameters.

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 ('Compare two product-feed snapshots') and the return shape ('added, removed, and changed commerce fields'), which is more than the title restates. It does not differentiate itself from siblings like catalog_audit or catalog_remediation, so an agent gets the what but not the 'why this one'.

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?

There is no when-to-use guidance, no prerequisites, and no named alternative among the nine sibling catalog/GTIN tools. The only usage-adjacent text is the price line, which is not a selection criterion.

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