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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds a genuinely valuable domain rule ('a met control without evidence is unknown, never certified'), which explains how status is normalized. It does not disclose scoring, output shape, or how the six pillars are aggregated, but the one rule it does add is meaningful beyond annotations.

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?

Two short sentences with no filler, and the evidence rule is front-loaded. But the brevity is under-specification rather than efficiency — the description is too thin to support correct invocation of a two-parameter review tool.

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?

An output schema exists, so return-value explanation is not required, but the description still fails to say what a 'review' does with the organized evidence (verdict? scoring? certification output?) or how the workload and controls parameters interact. For a review tool with 0% schema description coverage, this leaves material gaps an agent must guess around.

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 for undocumented parameters. It only obliquely references 'six pillars' (matching the pillar enum) and 'evidence,' but never explains the workload parameter, the controls array structure, status semantics, or the meaning of 'met/gap/unknown' input values. This leaves the required 2-parameter contract largely unexplained in prose.

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 'organize evidence by six pillars,' which conveys a specific action, and the name/title signal a Well-Architected review. However, it never states explicitly that the tool reviews a workload's controls against the six pillars or what output it produces, so an agent cannot fully distinguish it from siblings like cloudformation_review or code_review_architecture without 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?

No guidance on when to use this tool versus alternatives, no prerequisites, and no exclusions. The only hint is the mention of six pillars, which is implied context rather than routing guidance.

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