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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is partly covered. The description adds genuinely useful context beyond that: stop_follow_up and block also cancel the pending scheduled call and end the sequence, and resuming does not restore them — an irreversible side effect the annotations alone do not convey.

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?

Three dense sentences, front-loaded with the tool's scope before the action list and the side-effect caveat. Nearly every clause earns its place, though the second sentence is long and could be tightened.

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 does need to carry behavioral weight, and it covers scope, identification, and irreversible cancellation effects. It stops short of stating permission/auth requirements or what happens to in-flight calls, which a destructive multi-action tool could reasonably include.

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 description coverage is 100%, including a detailed enum explanation for action, so the schema already carries the parameter semantics. The description restates identification via lead_id or phone_number but adds no syntax, format, or precedence detail beyond what the schema provides — baseline 3 applies.

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?

Names a specific verb pair (stop/resume) and resource (automated contact with one lead), then enumerates the exact channels covered: follow-up calls, texts, AI calls/texts, and full block. An agent can distinguish this from siblings like cancel_scheduled_call or add_to_sequence without opening the 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?

Usage is implied through the action enumeration and the lead-identification instructions, and the side-effect note ('stop_follow_up and block also cancel...') helps an agent choose. However, it never contrasts itself with adjacent tools such as cancel_scheduled_call or add_to_sequence, nor states when one action should be preferred over another.

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