scout_hover

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

With no annotations, the description carries the full load and does well: it discloses the return shape, that results are diffed against pre-hover state, that each item is truncated to 300 chars, and that on busy pages new text may be unrelated and is labelled as such. It does not cover wait/timing behavior for animations or whether the hover is dismissed afterward, which are the remaining material gaps for this kind of tool.

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?

Front-loaded with the action and the payoff (what it reveals), then the caveats about truncation and possibly-unrelated text, then the usage directive. Dense and largely waste-free, though the second clause is a long run-on that could be split for scanability.

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?

There is no output schema, and the description compensates by describing the returned payload fields and their 300-char truncation. With no annotations, it also warns that results are state-diffed and may contain noise on busy pages. Complete enough to call correctly; only timing/teardown semantics are unstated.

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%, so both `ref` and `session` are already documented in the schema, including the concurrency rationale for multi-session dispatch. The description only echoes 'by ref' and adds nothing about the session parameter. Baseline 3 applies when the schema does the heavy lifting.

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?

States a specific verb (hover) on a specific resource (element by ref) and immediately enumerates what it returns: tooltips/popovers diffed against pre-hover state, new page text, title attribute, and aria-describedby. It is clearly distinguishable from scout_click and scout_snapshot, which it implicitly contrasts by noting hover-gated UI is invisible to them.

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?

Gives concrete application targets (badges, icons, truncated text, error indicators) and a strong directive: use BEFORE concluding an element 'does nothing'. It also clarifies the boundary condition that hovering does not count as exercising the element. It stops short of naming an alternative tool explicitly, but the snapshot/click contrast supplies the routing context.

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