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

Annotations already declare idempotentHint and destructiveHint, but the description adds real value beyond them: it discloses the return contract ('returns what was cancelled; status nothing_scheduled means it was a no-op'), the role gate ('owners and admins only' for bulk), and the side effect of ending the lead's sequence. The idempotent no-op semantics are especially useful given destructiveHint=true.

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?

A single dense sentence front-loads the core action and enumerates modes, with the bulk-confirm warning placed last. Every clause carries information, though the run-on structure is slightly heavy for readability.

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 100% schema coverage and no output schema, the description successfully covers what's needed: it explains the return/status semantics, the permission requirement for bulk cancellation, and the sequence-ending side effect. An agent has enough to invoke it correctly.

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 100%, so individual parameter docs are complete and the baseline is 3. The description earns above-baseline credit by explaining how the parameters interrelate: lead_id or phone_number identify one lead, scheduled_call_ids selects several (up to 500, each sequence ending too), and all scopes to team_id with an admin restriction.

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 (cancel) and resource (a lead's pending scheduled call), and goes further to clarify that it also ends the lead's follow-up sequence. The three distinct modes (single lead, by scheduled_call_ids, or all/team) are spelled out, letting an agent distinguish it from siblings like reschedule_call or delete_lead.

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 clearly delineates the three invocation modes and when each applies (lead_id/phone_number vs scheduled_call_ids vs all with team_id), plus the operational guardrail 'Confirm bulk cancels with the user first.' It stops short of naming alternatives such as reschedule_call for a callback the agent wants to move rather than cancel.

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