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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful context by disclosing the returned store fields (id, address, phone) and the hierarchical scoping behavior. It stops short of pagination or rate-limit detail, but for a read-only browse tool this is solid.

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?

A single dense sentence, front-loaded with the resource and followed by the mode breakdown, with zero filler. The sibling comparison is appended efficiently rather than consuming its own paragraph.

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-value documentation is not required. The description nonetheless names the key store fields and covers all three invocation modes plus the sibling distinction, leaving nothing an agent needs in order to call it correctly.

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 goes further by explaining the behavioral consequence of each parameter state: no params returns all states with counts, state returns that state's cities, city returns stores. That mode-to-parameter mapping is meaning the schema descriptions alone do not convey.

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 (browse) and resource (Arby's US store directory), then enumerates the three distinct operating modes (all states, one state's cities, one city's stores). It also explicitly distinguishes itself from the sibling arbys_locations ('No coordinate needed'), so an agent can route without opening either 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?

The description maps each parameter combination to a use case and names the alternative tool (arbys_locations) with the exact condition that selects against it (coordinate-based lookup). When-to-use is fully covered, with the sibling exclusion spelled out.

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