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

The description carries the load that annotations cannot: it discloses the two-phase confirmation workflow ("returns a preview... and a confirmation link. Only the merchant, on that page, can make it happen"). This is exactly the context an agent needs to avoid assuming an immediate write, and it goes well beyond the readOnlyHint=false / destructiveHint=false 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?

Front-loaded with the purpose, then the preview behavior, in four tight sentences. The stray money/cents sentence is irrelevant to any parameter in this schema and is the one piece of noise.

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?

For a 10-parameter, nested-object tool with no output schema, the description correctly explains the return (a preview plus confirmation link) and the confirmation gating. Combined with the rich schema descriptions for lat/lng, hours, tags, and store, this is nearly complete; the missing piece is routing guidance relative to siblings.

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 80%, so parameters are largely self-documented. The description's only parameter-adjacent note ("Money is integer minor units") refers to no field in the schema, adding no useful semantics. Baseline 3 is appropriate.

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?

"Put a store on the map or change it" gives a concrete verb (put/change) and resource (store), which distinguishes it cleanly from store_locator_stores (list) and store_locator_remove (delete). It does not name those siblings explicitly, so it stops short of a 5.

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?

No when-to-use versus alternatives is stated. The description doesn't tell the agent how this relates to store_locator_stores, store_locator_remove, or pickup.set_location (that dependency is only hinted at inside the schema's store param). Usage is left to inference from the tool name.

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