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

Annotations already establish this is a read-only, non-open-world call. The description adds useful behavioral context beyond them: the result includes a URL that must be surfaced to the user to continue buying the policy, which tells the agent what to do with the output. It doesn't discuss failure modes beyond the schema's expiry note.

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?

Three tight sentences, front-loaded with the action, followed by parameter sources and the required user-facing follow-up. No filler or redundancy.

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?

The tool is simple, both required parameters are fully documented, an output schema exists, and the description covers the workflow position and the one action the agent must take with the result. Nothing material is missing for correct invocation.

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 the schema already documents both parameters, including the expiry of quote_handle and the provenance of quote_id. The description repeats that provenance rather than adding new syntax or constraints, so 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?

States a specific verb and resource: 'Get the next step for the quote the user chose.' It also references both sibling tools (zebra_start_session and zebra_get_rc1_rates) as the sources of its inputs, so the agent can distinguish it from them immediately.

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 gives clear workflow sequencing: pass quote_handle from zebra_start_session and quote_id from zebra_get_rc1_rates, then relay the returned URL to the user. It doesn't state explicit when-not conditions or error alternatives, but the orchestration context is clear.

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