Update, start, pause, resume or cancel a campaign

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

Annotations only declare openWorldHint and idempotentHint=false, so the description carries most of the behavioral burden — and it does add real value: "kicks the dialer right away - real calls start going out" discloses a consequential external side effect, and it notes the campaign.status_changed webhook. It omits reversibility of "cancelled" (stated as permanent, which is good) and permission requirements.

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?

Compact and front-loaded: the core action comes first, then the status semantics, then the webhook side effect. Slightly awkward inline quoting of "status:"running"" but no wasted sentences.

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 non-idempotent mutation with an open-world hint, no output schema, and 5 undocumented parameters, the description covers the status side effects and webhook well but leaves the settings-oriented parameters (name, concurrency, budgetCapCents) and the remaining enum values unexplained.

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 0%, so the description must compensate. It explains three of the six status enum values (running/paused/cancelled) but ignores completed/scheduled/draft, and says nothing about name, concurrency, or budgetCapCents. Partial compensation, so a mid score.

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 states a concrete verb+resource ("Change settings, or change status") and the title enumerates the operations (update, start, pause, resume, cancel). It is clear what the tool does, though it doesn't distinguish itself from siblings like delete_campaign or create_campaign beyond the operations listed.

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 only implied: the status values hint at when to start/pause/cancel, but there is no explicit guidance on when to use this versus delete_campaign (cancel vs delete) or create_campaign, and no prerequisites stated. The one hard constraint (campaignId required) comes from the schema, not the text.

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