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

Annotations declare destructiveHint=true, readOnlyHint=false, openWorldHint=true, idempotentHint=false. The description does not mention that this posts visible content to a worker's page, that it is non-idempotent, or what side effects occur. It also fails to explain that task_id must be an active interactive task. With such a strong annotation profile, the description should say more about the write/visibility implications.

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?

It is a single concise sentence with no waste, but it is too terse for a tool with four parameters and a non-trivial side effect. Front-loading is fine, but more substance is needed.

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?

For a destructive, open-world, non-idempotent tool that mutates a worker's interactive page, the description is incomplete. It omits prerequisites (interactive task required), error conditions, and the fact that regions and caption are optional overlays. No output schema exists, so the description must carry more of the behavioral burden.

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 100%, so the parameters caption, regions, task_id, and frame_id are fully documented in the schema. The description adds only a colorful example ('this avocado, not that one') for the caption, without additional semantics beyond what the schema provides. Baseline 3 is appropriate.

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 says 'point at something' and that a frame appears on the worker's page with boxes and a caption. This is evocative but does not state a precise verb+resource like 'display a captured frame to a worker'. It is distinguishable from siblings like capture_frame, but only loosely.

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 explicit when-to-use or when-not-to-use guidance, and no mention of alternatives such as capture_frame or send_chat_message. The agent must infer from the framing alone that this is for interactive pointing.

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