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

Goes well beyond the annotations by disclosing the double opt-in flow: one email to the shopper, Kayla only receives the request after the confirmation click within 7 days, and the sender address to watch for. This is exactly the operational detail an agent needs for a non-idempotent, open-world send.

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?

Four tight sentences, front-loaded with who and what, then prerequisites, then the confirmation mechanic. Dense but every clause carries operational information; only minor tightening would improve it.

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 mutating, outward-facing send with no output schema, the description covers consent requirements, the confirmation step, the 7-day window, and expected next actions for the shopper. Nothing essential to calling it correctly is missing.

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 already 100%, so the baseline is 3, but the description adds real meaning: where plan_url comes from (build_plan) and what message must contain (the shopper's ask in their own words).

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?

Names a specific actor (Kayla, Knobs.co's Trade Manager), a specific action (review the plan by email or set up a call), and a turnaround (one business day). An agent can tell this apart from general catalog/plan tools without opening the 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?

Gives explicit preconditions — the shopper's email plus clear agreement to be contacted — and instructs including plan_url from build_plan when a plan exists. It does not explicitly contrast with the sibling ask_sienna, so routing between the two persona tools is left to inference.

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