SmartProspect: find emails (consumes credits)

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

Annotations indicate non-read-only and non-destructive, but the description adds critical context: consumes credits, creates/modifies remote state, maximum 10 contacts, never retried automatically to avoid double charging, and the endpoint. This goes well beyond the structured annotations.

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?

Every sentence serves a purpose: purpose, safety, endpoint, limits, prerequisites, retry policy, and credit-check reminder. The structure front-loads the core function and uses a compact safety summary line, making it efficient and easy to scan.

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?

Although an output schema exists, this tool has unusual complexity (credit spending, env var requirement, non-read-only behavior). The description covers usage limits, prerequisites, safety, retry policy, and points to a sibling tool for credit balance, leaving no critical gaps for agent 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 covers all three parameters at 100% coverage, but the description adds operational semantics: the 10-contact limit, the mandatory firstName/lastName/companyDomain trio, and the environment variable gate for confirm_credit_spend. It reinforces the critical flag without duplicating schema text.

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 clearly states the tool's purpose: 'Look up email addresses for up to 10 named contacts at their company domains.' This is a specific verb+resource+scope that differentiates it from sibling tools focused on broader searches or analytics.

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 explicit preconditions: requires SMARTLEAD_MCP_ALLOW_CREDIT_SPEND=true and confirm_credit_spend: true, and advises checking smartprospect_get_search_analytics first for credit balance. It doesn't contrast with search_contacts alternatives, but clearly states when the call will be refused locally.

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