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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so safety is fully covered by structured data. The description adds nothing beyond them: no pagination behavior, no default date window when from/to are omitted, no indication of result volume or ordering, all of which matter for a list endpoint with a limit capped at 100.

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?

The single sentence is front-loaded and contains zero waste, but it is too terse rather than well-sized: the same brevity that makes it clean is what leaves the usage and pagination gaps. Efficient, not complete.

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 five parameters, no output schema, and no annotations gaps, the description should at minimum explain the date-range and pagination semantics and what a report record contains. Annotations carry the safety profile, which offsets some of the shortfall, but a list tool with a capped limit needs more than one sentence.

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 coverage is only 60%: id, from and to are documented, but limit and offset carry no schema descriptions. The description says only 'for a domain', which restates the required id, and gives no hint about date-range filtering, pagination, or default values, 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 specific verb ('List') and a specific resource ('DMARC forensic (failure) reports') scoped 'for a domain', and the parenthetical clarifies what forensic means. It is clearly distinguishable from list-dmarc-reports and get-dmarc-forensic-report in substance, but it never names those siblings, so differentiation is left to the agent's inference.

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 when-to-use guidance: no statement about opting for this vs. list-dmarc-reports (aggregate) or get-dmarc-forensic-report (single record), and no mention of prerequisites such as a verified domain or a prior list-domains call to get the required id. Usage is only implied by the verb.

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