Capture an in-memory browser image

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds a genuinely useful trait—'short-lived in-memory'—explaining that the image handle is transient, but it does not go further (e.g., lifetime, retrieval path).

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?

Single sentence, front-loaded with the action verb; no filler or redundancy. It earns its place and is easily parsed.

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 5 parameters, no output schema, and zero parameter descriptions, the single sentence is not enough to call the tool correctly. The agent is left guessing the semantics of the three required integer/epoch fields and the handle's lifecycle.

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%, and the description does not explain target_id, target_epoch, scope_revision, ref, or return_image. The phrases 'viewport or one element' hint at a target selection but do not map to any parameter, leaving five parameters effectively undocumented.

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 ('Capture'), a specific resource ('the viewport or one element'), and an outcome ('a short-lived in-memory image handle'). It is clear and unambiguous, though it does not explicitly contrast with sibling tools such as observe or verify.

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 is provided on when to use capture versus alternatives like observe, verify, or list_targets. It only describes what the tool does, not when to choose it or when to avoid it; no exclusions or alternative tool names appear.

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