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

Annotations already mark this readOnly and openWorld, so the safety profile is covered. The description adds genuinely useful context beyond them: the result ordering (nearest first), the contents of each result, and the cross-tool linkage that each store_id prices arbys_menu. It says nothing about rate limits or auth, but for a benign read tool that is a minor gap.

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: the first front-loads what it returns, the second carries the cross-tool linkage. No filler, no repetition of the name.

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 need not be enumerated, yet the description still names the key fields, which helps the agent judge fitness. Combined with 100% schema coverage, this is complete enough for a 5-param read tool, with only the missing sibling routing keeping it from the top mark.

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% and each parameter is documented in the schema, including the radius cap and pagination semantics. The description only restates that a radius and a coordinate exist, adding no syntax or constraint detail beyond the schema, 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 ('Arby's restaurants within a radius of a coordinate') plus scope details (nearest first) and returned fields, so the agent knows exactly what this does. It references the arbys_menu sibling via store_id, but never contrasts itself with arbys_location or arbys_directory, so sibling disambiguation is only implicit through the plural name.

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 coordinate-plus-radius framing implies the use case (proximity search around a point), but there is no explicit when-to-use statement and no guidance on when to prefer arbys_location or arbys_directory instead. Usage is inferable rather than stated.

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