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 adds genuinely useful behavioral context beyond them — that rating, price range, delivery fee and ETA are omitted rather than estimated when upstream does not report them, and that absence should be read as 'not-reported'. It does not cover pagination or ordering behavior, but the data-quality caveat is real added value.

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?

Three tight sentences, front-loaded with what the tool is, then the return fields, then the omission caveat and the location requirement. No filler; each sentence 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 only needs to add non-structural context, and it does — the upstream-reporting caveat is exactly the kind of thing schema and annotations cannot express. Pagination semantics for limit/offset are the only notable gap.

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 limit, offset, latitude and longitude. The description only restates that latitude/longitude are required and adds nothing about limit/offset semantics or expected coordinate format, 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?

States a specific verb and resource — a location-aware nearby-store discovery feed — and enumerates the returned fields (store ID, name, cover image, tags, rating, price range, delivery fee, ETA). It is distinguishable from doordash_search and doordash_store, but it never names those siblings explicitly to sharpen the contrast.

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?

Usage is only implied: 'nearby-store discovery' plus the note that latitude and longitude are required tells the agent this is a location-scoped browse call. There is no explicit when-to-use vs when-not, and no routing to alternatives like doordash_search or doordash_store.

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