Inspect the Flow UI

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

With annotations already signaling readOnlyHint=false and openWorldHint=true, the description adds meaningful behavioral context by explaining the snapshot-action-diff flow and the exclusion 'Never generates anything.' It could further disclose side effects of actions like click/type/goto, but the annotations and action list already imply mutability.

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 compact and front-loaded with the core behavior in the first sentence. The extra sentences about selector discovery and 'Never generates anything' are useful context, though the bug-report mention is slightly tangential.

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?

The tool is complex with 12 parameters, but the schema covers most of them and an output schema exists. The description supplies the missing usage context and distinguishes the tool from generation/screenshot siblings, making it sufficiently complete for an agent to invoke 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?

The input schema covers 83% of parameters with descriptions, so the baseline is 3. The description adds minimal parameter-level meaning beyond noting click/hover by text or aria-label regex and pressing keys or navigating, which mostly restates schema information already present.

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 and resource: it snapshots interactive elements, optionally performs one action, and returns elements that appeared/disappeared. It also clearly differentiates from siblings like flow_screenshot and flow_generate_* by emphasizing selector discovery and 'Never generates anything.'

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?

The description gives clear context on when to use this tool: 'This is how selectors are discovered when Flow changes its UI.' It lacks explicit when-not-to-use instructions or named alternatives, but the strong purpose statement and sibling context make the intended use evident.

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