Observe structured browser state

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

Annotations already establish readOnly, idempotent, non-destructive behavior, so the burden is lower. The description adds useful behavioral context: results are 'visible DOM-backed controls', refs are 'strict', and an optional revision-diff mode exists. It does not explain ref stability or dynamic-page caveats, but it goes beyond the 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?

The description is a single sentence with no filler words and is front-loaded with the primary return value. However, it may be overly terse given the presence of 4 parameters and a dual-mode behavior. It is concise but sacrifices necessary parameter context.

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?

Given no output schema and 4 undocumented parameters, the description is incomplete. It fails to clarify what 'strict refs' means, how revision diffs are triggered, what max_depth and max_nodes control, and how the return value should be interpreted. The rich annotations help safety but not operational completeness.

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 the 4 undocumented parameters. It does not explain target_id, max_depth, or max_nodes; only 'revision diff' hints at since_revision. This is insufficient for an agent to know how to populate parameters correctly.

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 uses a clear verb ('Return') and specifies the resource: visible DOM-backed controls with strict refs, or a revision diff. The title reinforces the domain. However, the 'or a compact revision diff' clause introduces mode ambiguity and does not explicitly distinguish this from sibling tools like 'capture' 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 given about when to use 'observe' versus alternatives such as 'capture', 'verify', or 'wait_for'. There is no explicit when/when-not language, and the reader must infer from the tool name that it is for inspecting browser state. This is implied usage at best.

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