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

Annotations already declare readOnlyHint=true and openWorldHint=false; the description goes well beyond that with append-only semantics, newest-first ordering, permission scope, pagination mechanics, timezone requirement, and operational caveats (accepted ≠ provider completion, history begins at audit enablement, agent labels self-reported). This is exactly the extra context annotations cannot convey.

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?

Front-loads purpose and the core scoping rule (omit domain), then flows through permission, ordering/pagination, timestamp format, and event-semantics caveats. Every sentence adds distinct information with no repetition.

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?

Output schema exists so return shape need not be described, and the description covers permissions, pagination, timezone rules, and result interpretation. The main residual gap is the unexplained 'action' filter and limit semantics for a zero-coverage schema.

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 domain (omit for portfolio), cursor (reuse same filters), and from/to timestamps (require timezone), which is meaningful added meaning. It does not explain the action filter or limit behavior, leaving two of six parameters undocumented anywhere.

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 and resource (read append-only domain change history) plus scope (authenticated customer, per-domain or portfolio-wide). No sibling tool in the list exposes audit/history data, so it is unambiguously distinguishable from the DNS/contact/registration siblings.

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?

Gives concrete usage conditions: omit domain for portfolio history, requires audit:read, pass next_cursor with the same filters for another page, and timestamps must include a timezone. It lacks explicit when-not-to-use guidance or named alternatives, but no sibling overlaps, so the remaining gap is small.

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