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 adds meaningful context beyond them: the return payload is summaries with image URLs/refs and not the images, and results are owner-scoped to the caller's account.

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?

Three tight sentences, front-loaded with what the tool lists, then what it returns, then the default and scope. Every clause earns its place and nothing is repeated.

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 no output schema, the description supplies the missing return-shape information (summaries with image URLs/refs, not images). Defaults and ownership scoping are also covered, leaving nothing an agent needs in order to call it correctly.

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 100% and the replay_id description already explains its narrowing intent in detail, so the schema carries the load. The description's 'defaults to pending' restates the status enum default rather than adding new semantics, warranting the baseline 3.

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?

Specific verb (List) plus a precisely described resource (AI Visual Review candidates = flow-replay steps where perceptual pixel-diff flagged changes against an approved baseline). It also explicitly differentiates itself from get_visual_review, so an agent can route correctly without opening either schema.

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?

States the default behavior (pending/unreviewed candidates) and names the sibling to use when the images themselves are needed, which is clear contextual guidance. It stops short of stating when-not-to-use it (e.g. vs visual_compare or flow_replay_summary), so it is strong but not fully explicit.

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