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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds genuinely useful behavior: the 'biggest fall first' sort order, the 28-day hold precondition, and the returned fields (old price, new price, tracked link).

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. The eligibility criteria and sort order are front-loaded, and the filter affordances come second. Every clause carries information.

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 no output schema, the description usefully explains what each result contains (old/new price, tracked link), covering the return-value gap. It is largely complete, though it says nothing about the default limit or result-count behavior.

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 the schema already documents all six parameters with examples. The description only gestures at the same filter categories (search words, type, store, price) without adding syntax or format detail, so the 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?

Names a specific resource (products with recent price drops) and defines the exact selection criteria: a fall within the last 30 days from a price held at least 28 days. This is clearly distinguishable from generic siblings like search_products or get_store_offers.

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?

States the narrowing dimensions (search words, product type, store, price), which tells the agent how to scope a call. However, it never names an alternative sibling or says when NOT to use this in favor of search_products, so it stops short of full routing guidance.

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