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

With no annotations, the description carries the full burden of behavioral disclosure. It does disclose that the tool returns a confirmation message and that CaptchaToken is not required for MCP submissions, which is useful context. However, it does not mention side effects (e.g., whether this creates a CRM record, sends an email) or any irreversible/duplicate submission risks, which are relevant for a write operation.

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?

The description is only three sentences, with the primary verb and resource front-loaded. Every sentence adds value: the first identifies the action and context, the second clarifies the return value, and the third addresses a potential ambiguity about CaptchaToken. There is no redundant or filler content.

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?

Given the simple nature of the tool, complete parameter schema, and no output schema, the description covers the essential context for correct invocation: the purpose, the consent precondition, the return type, and the captcha quirk. It does not discuss error behavior or duplicate submission, but for a basic lead form tool this is a reasonable level of completeness.

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 schema already provides 100% coverage for all five parameters, so the baseline is 3. The description adds the 'CaptchaToken is not required' note, which relates to a parameter not in the schema, and implies the lead must have explicitly asked to be contacted, but it does not add meaning to the existing parameters themselves. The schema handles the heavy lifting.

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?

The description opens with a clear verb and resource: 'Submits a lead/contact form to Walnai' and adds a specific condition ('prospective client who explicitly asked to be contacted'). It clearly distinguishes this from the sibling tools, which are all read-only get/list operations. This is a precise, unambiguous purpose statement.

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 provides a clear usage condition: only submit for a prospective client who explicitly asked to be contacted. This signals consent requirements and helps the agent decide when to invoke the tool. However, it does not explicitly name alternatives or state when not to use the tool, though the sibling context (all info-gathering tools) makes the distinction implicit.

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