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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds genuine behavior beyond them: a hard cap of 100 events and newest-first ordering, which materially affects how an agent should interpret completeness of results. It does not state what happens if the campaign has no activity or whether the cap truncates silently.

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, zero filler, and the most decision-relevant facts (result cap and ordering) are packed in without padding. Nothing in it is redundant with the name or title.

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 simple single-parameter read tool with no output schema, the description does the heavy lifting by describing the result shape (event type and time) and ordering. Gaps are minor: the id's referent and empty-result behavior are left implicit.

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?

There is a single required nested parameter 'id' with 0% schema description coverage, so the schema supplies a UUID type but no meaning. The description only implies the id is a campaign identifier by referring to 'the campaign's activity' — it never states that explicitly or says what happens for an unknown id. Small but real added meaning over a bare UUID field.

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 specific verb and resource ('Returns the campaign's ... activity events') plus the scope of the result set. It does not explicitly distinguish itself from similarly named read siblings such as getCampaignDecisions or getCampaignReviews, which an agent could plausibly confuse it with.

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 gives no when-to-use guidance, no prerequisites, and no named alternatives. An agent must infer from the name alone that this is the tool for recent campaign event history rather than decisions, reviews, or messaging content.

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