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

Annotations already declare a non-destructive write to an open world. The description adds substantive behavior beyond them: the account must hold a Sales Navigator seat, the lead is created in Sales Navigator itself and must be removed there, and each call consumes a daily allowance of 100. That covers auth prerequisites, side-effect location, and rate limits.

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?

Front-loads the action ('Save ONE person as a lead'), then prerequisites, then side effects. The bracketed ids-in/ids-out prefix is a terse convention that fits the family. Dense but no wasted sentence.

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?

With no output schema, the description correctly notes 'Ids out: none' and explains the lifecycle (created in Sales Navigator, removed there) and the per-day cap. Nothing critical for correct invocation is missing, though it could note what a failed save returns.

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 all three parameters are documented structurally. The description restates the 'ACw…' id format and the optional-list behavior, matching rather than extending the schema. 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 ('Save ONE person as a lead in your Sales Navigator') plus optional scope (into a lead list). An agent can distinguish this from search_linkedin_sales_navigator_people or list-related siblings without opening any 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 clear context for use: requires a Sales Navigator seat, and the input must come from a search_linkedin sales_navigator result or a Sales Navigator lead URL. It stops short of naming an explicit alternative or a when-not-to-use condition.

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