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

Annotations declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is covered, but the description adds no behavioral context whatsoever: no note that changes are applied immediately, whether they are reversible, or that replacing mailboxes alters live sending. With annotations already doing the safety work, the bar is lower, yet the description still contributes nothing beyond the title.

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?

It is a single front-loaded sentence with zero filler, which is structurally clean. But for a 17-parameter mutation tool the brevity crosses from concise into under-specified, so the sentence does not really earn its place as the tool's only guidance.

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?

Given a 17-parameter mutation tool with no output schema, minimal annotations, and only 59% schema description coverage, the one-sentence description is far too thin. An agent cannot infer partial-update semantics, side effects on live campaigns, or the meaning of the undocumented parameters from this definition.

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 59%, leaving roughly seven parameters (name, windowStart/windowEnd, trackOpens, trackClicks, espMatching, stopOnReply) with no documented meaning in either the schema or the description. The description mentions 'schedule, mailboxes and options' at such a high level that it adds no semantic detail beyond what the schema already encodes, so it fails to compensate for the coverage gap.

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 a verb (rename/change) and a resource (campaign) plus rough field groups (schedule, mailboxes, options). However, it is a verbatim restatement of the title and 'options' is a catch-all that tells an agent nothing about the 17 mutable fields. It also does nothing to distinguish this tool from siblings like pause_campaign, set_sequence, or launch_campaign, which also alter campaign state.

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?

There is no guidance on when to use this tool versus pause_campaign, launch_campaign, set_sequence, or write_sequence, and no statement of prerequisites (ownership, permissions, campaign state). Critically, it never says whether this is a partial update (omitted fields preserved) or a full replacement, which is the single most important routing decision for a 17-parameter mutator.

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