element_to_selector

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

With no annotations provided, the description bears the full transparency burden. It discloses the dependency on a prior snapshot/diff and defines the output as a unique CSS selector. It does not cover failure modes or exact return type, but these are minor for a simple conversion 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?

The description is a single sentence that leads with the core action and resource, then provides the prerequisite. Every word is necessary and there is no redundant information.

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 single-parameter tool with no output schema, it is mostly complete: it states what is returned, the required prior step, and the automation use case. The main gap is that it doesn't mention the return format (e.g., string) or error behavior, but these are not critical for the tool's intended use.

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%; the only parameter 'uid' is already described as 'Stable uid from the snapshot output.' The tool description merely reinforces 'snapshot uid' without adding new meaning, so it stays at the baseline of 3 with no additional semantic contribution.

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 specific verb 'Return' and clearly defines the resource: a unique CSS selector for a snapshot uid. It also names the intended downstream use (chrome-devtools-mcp click/fill), which distinguishes it from sibling tools like get_node or snapshot_index that likely return node data rather than selectors.

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?

It explicitly states a precondition (requires smart_snapshot or snapshot_diff first) and identifies the use case (for click/fill). It does not explicitly name alternatives or exclusions, but the context makes it clear when to use this tool, which is adequate for this utility.

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