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

Annotations declare readOnly/idempotent/non-destructive, so safety is covered, but the description adds substantial context: it enumerates the outcome values (likely, likely_if_member, unlikely, check, no_drop), what extra fields appear conditionally (links with an item name, claim_message for likely claims), and the policy.refund_paid_as store-credit flag. It stops short of discussing rate limits or anything about auth, but the behavioral payoff is rich.

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?

Front-loaded with the core purpose and outcome list, then the example, then the conditional extras; every sentence carries information. It is a touch long and the title question is echoed at the start, but there is no real filler.

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 takes on the burden of explaining returns and does so thoroughly: outcome values, amount, steps, conditional links, claim_message, and the store-credit flag. All 7 parameters are schema-documented and annotations cover the safety profile, so nothing an agent needs to call this correctly is missing.

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 every parameter including ranges, country behavior, and the purchase_date-vs-days_since_purchase relationship. The description's notes on item-driven links and purchase_date deadlines largely restate what the schema already says, so it adds only marginal meaning. Baseline 3 is appropriate.

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 gives a specific verb+resource (checks whether a price-drop claim is likely, returns outcome, amount, and steps) and enumerates the possible outcomes, which is far beyond the title's restatement. It does not explicitly name or contrast against its siblings (get_store_policy, get_claim_reminder, list_stores, cheapestprice_check_price), so an agent must infer the boundary itself.

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 worked example ('I bought a TV at Best Buy 9 days ago for $499 and it's $449 now') concretely establishes the situation this tool is for, effectively implying when to call it. However, there is no explicit statement of when NOT to use it or which sibling to pick instead (e.g. get_store_policy for raw policy, get_claim_reminder for follow-ups).

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