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

Annotations fully cover the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), so the burden is lightened. The description contributes one genuinely new behavioral fact — the Premium eligibility requirement — but says nothing about what a list returns, pagination, or that person requires a key.

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?

Two short, front-loaded sentences with no filler; the resource and available actions come first. The help-invocation note is somewhat redundant with the schema's params description, costing a little.

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 multi-action dispatcher with a nested freeform params object and no output schema, the description is thin: it does not say what person requires, what list returns, or how many contacts to expect. The Premium note and help pointer are helpful but not sufficient to fully guide 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 coverage is 67%: the action enum is self-explanatory and person_key carries its own description and pattern. The description adds the help-action discovery mechanism, which is useful, but it does not explain the freeform params object or how it differs between list and person.

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 names the resource (the member's contacts and one person's profile) and enumerates the actions (list, person), so an agent can tell this reads contact data rather than mutating it. It does not name the manage_contacts sibling as the write counterpart, so sibling differentiation is only implicit.

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?

It tells the agent how to discover per-action fields (action "help") and flags a Premium gate, which is useful context. It never states when to use this versus manage_contacts, get_outreach, or get_profile, so routing 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.