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

With no annotations supplied, the description carries the burden and does meaningful work: it discloses the consequence of omitting contact (request counted anonymously, user continues via the WhatsApp link) and imposes a consent constraint on passing contact data. It never states explicitly that this is a write/registration side effect with rate limits or idempotency, which keeps it below a 5.

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?

Purpose and the WhatsApp outcome are front-loaded in the first sentence, and the second paragraph is a tight parameter walkthrough. Every sentence carries distinct information, with no restatement of the title or filler.

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 5-parameter, 1-required tool with no output schema, the description covers the invocation prerequisites, the return artifact (WhatsApp link), and the privacy gate on contact. Only the 'note' parameter and any sense of what the registration actually creates or how often it can be called are left unaddressed.

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 0%, so the description must compensate and largely does: product_id's provenance, business_type with a concrete example ('pharmacy with 2 locations'), location as city/country, and contact's format and consent rule are all clarified. The 'note' parameter is never mentioned, leaving one of five parameters with no semantic guidance in either the schema or the description.

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 ('Register a user's interest in a Vira product or request onboarding') plus the concrete outcome ('get a direct WhatsApp link to Vira's team'). It also differentiates itself from vira_list_products by naming it as the source of product_id, so an agent can place it without opening a sibling 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?

Establishes the prerequisite chain explicitly: product_id must come from vira_list_products, and contact is conditional on the user having explicitly provided it for this purpose. It gives clear context for invocation but does not contrast against alternatives such as vira_recommend_solution or vira_pricing, so it stops short of full when/when-not guidance.

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