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

Annotations already declare readOnlyHint, idempotentHint, and a closed-world scope, so the safety profile is covered. The description adds genuine context beyond that by disclosing the returned payload fields (price, delivery window, required inputs, exclusions, intake URL), which matters because no output schema exists. It stops short of describing ordering, pagination, or lookup cost.

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, both fully loaded: the first front-loads the usage gate before any alternative is offered, the second enumerates the return contents and the downstream tool. No filler or restatement of the title.

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 no parameters and no output schema, the description carries the return-value burden itself and does so by naming the payload fields. Combined with the routing guidance to find_service and get_acceptance_tests, an agent has everything needed to call this correctly and place it in a workflow.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate; the baseline for a parameterless tool is 4. The description correctly avoids inventing filter semantics that the empty schema contradicts.

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?

Specific verb+resource with explicit scope: enumerates 'Zinvyl's full seven-offer catalog', which tells the agent exactly what set is returned. It distinguishes itself from siblings by naming find_service as the different starting point and get_acceptance_tests as the follow-on step.

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?

Gives an explicit precondition ('Use only when comparing ... full seven-offer catalog'), an explicit fallback ('otherwise start with find_service'), and explicit sequencing ('use get_acceptance_tests only after selecting an offer'). When, when-not, and alternatives are all present.

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