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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description still adds useful behavioral context the annotations lack: the index scale (9,700+), the three-variant structure per store, and the edge case that pages past the end return an empty list.

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?

Four short sentences, front-loaded with purpose, then filtering semantics, then the empty-list edge case, then the alternative tools. No sentence 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?

An output schema exists so return values needn't be described, yet the description still covers the notable empty-list case. Read-only safety is covered by annotations and alternatives are named, leaving nothing an agent needs 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 coverage is 100%, so the baseline is 3, but the description adds meaning beyond the schema's terse enum by explaining that kind=sandwiches yields one canonical entry per store. It does not explain shard/page/page_size interplay beyond what the schema already says.

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 (List) and resource (pages from Jimmy John's sitemap store-URL index), and immediately scopes it with the filterable fields. It also names the sibling tools for location lookups, so the agent can distinguish it from jimmy_johns_nearby/jimmy_johns_store without opening the schema.

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?

Gives the exact condition for the key filter ('use kind=sandwiches for one canonical entry per store') and explicitly routes location queries to jimmy_johns_nearby or jimmy_johns_store. Both when-to-use and when-not-to-use are covered.

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