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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds a genuinely useful behavioral note that omitted store_id yields placeholder national promos, warning the agent about low-value results. It does not mention rate limits or caching, but adds context beyond the annotations.

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 tight sentences that front-load the resource and payload, then the usage caveat. No filler; 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 an output schema present and annotations covering safety, the description supplies everything needed to call the tool correctly: what it returns, the US/Canada scope, and how store_id changes results. No critical gap remains.

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 coverage is 100% and the schema description already explains store_id points to a store from the store/nearby endpoints and that omission returns national promos. The description reinforces this but adds no syntax or format details beyond the schema, 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?

States a specific resource (Papa John's US/Canada store promotions) and enumerates the returned fields (code, title, offer/regular price, deal-builder link). The US/Canada scoping meaningfully distinguishes it from region siblings like papajohns_intl_deals and papajohns_intl_offer.

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?

Explicitly tells the agent to pass a store_id and explains the consequence of omitting it (national promotions are largely placeholders). It stops short of naming alternative siblings for non-US/Canada or nearby-store lookups, so it's clear on context but not on exclusions.

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