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

The annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds genuinely useful behavioral nuance beyond that: size is only present 'when the florist network publishes it', and the response includes tax-inclusive totals, a substitution policy and delivery terms — expectations an agent would otherwise have to discover by trial.

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 sentences, front-loaded with the action and lookup key before the field inventory. The long run-on enumeration of returned fields partially duplicates the output schema, which is the only wasted effort.

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 single-parameter read tool with an output schema and full annotation coverage, the description supplies what is needed to invoke it correctly and know what to expect. Only the error/not-found path and the upstream source of the code are left unstated, which is a minor 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 coverage is 100% and the single parameter already carries an example ('T163-1A'). The description only restates that the lookup is by product code, adding no format, casing, or validation 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 ('Return full details for one arrangement') with an explicit retrieval key (product code) and enumerates exactly what comes back. It reads clearly against the sibling search_arrangements, since the singular 'one arrangement by product code' signals a detail fetch rather than a search.

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?

'Use it to show a customer exactly what they are buying' gives a concrete decision context for calling the tool. It does not, however, say where the code comes from (presumably search_arrangements) or what to do when a code is unknown, so no exclusions or alternatives are stated.

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