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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds genuinely non-redundant context: it requires authentication, and crucially warns that sent/replied figures are recorded workflow labels rather than independently verified delivery or human-reply totals — a data-quality caveat an agent would otherwise misread.

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?

One sentence, front-loaded with the verb and resource, with the qualification clause tacked on at the end. It earns its length by carrying the verification caveat, though the compound 'not independently verified delivery or human-reply totals' phrasing is dense enough to slow parsing.

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 present, the description responsibly summarizes the returned payload (campaigns, lead counts, sent/replied labels) and flags the authentication requirement. The main omission is any hint about ordering, pagination, or empty-result behavior, but for a zero-parameter list tool this is reasonably complete.

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?

The tool takes zero parameters, so the baseline is 4. The description correctly does not invent parameter semantics, and instead spends its words on the shape of the result set.

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 (List) and resource (outreach campaigns), scoped to the authenticated user, and enumerates what the records carry (lead counts, sent/replied workflow labels). It is clearly distinct from mutation siblings like create_outreach_campaign, though it never names the closest read alternatives (list_campaign_replies, outreach_analytics) for contrast.

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 rather than stated: an agent can infer this is the enumeration tool for campaigns, and 'Requires authentication' is a precondition. But there is no explicit when-to-use guidance versus outreach_analytics, list_campaign_replies, or list_campaign_triggers, all of which sit in the same campaign domain.

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