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

Beyond the annotations (read-only, idempotent, non-destructive), the description discloses ordering (oldest first), filtering (optionally since a date), and pagination (paged by cursor). It also notes events are 'URL'd', hinting at output structure. These are valuable behavioral traits not covered by annotations, so the description adds meaningful context.

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, compact sentence packs in the core purpose, event types, ordering, optional filter, and pagination. Every phrase adds value and the key scoping ('one record') is front-loaded. No fluff or redundancy.

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 read-only list tool with an output schema and solid annotations, the description covers the essential operational details: scope, event categories, ordering, optional date filter, and pagination. The required identifier is implied by 'one record' and documented in the schema. Minor gaps like limit explanation are covered by schema defaults, so the description is sufficiently 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?

Schema description coverage is 75% (since, cursor, identifier have descriptions). The description echoes 'optionally since a date' and mentions pagination, but does not add new meaning beyond what the schema already provides for the since and cursor parameters. It adds no detail on limit or identifier. With high coverage, the baseline of 3 is appropriate.

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 ('list') and resource ('events on one record'), with concrete event types and ordering ('oldest first'). It is clearly distinguished from sibling tools by its focus on events, even without naming alternatives. The scope 'one record' adds clarity.

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?

The description explains what the tool does but gives no guidance on when to use it versus alternatives like get_record or list_aliases. It mentions 'optionally since a date' as an option, but does not frame the selection context or any exclusions. An agent would have to infer when this tool is the right choice.

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