listFrames

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

No annotations are provided, so the description carries the full burden. It discloses the output fields (url/name/isMain and active frame) and the purpose of discovering cross-origin iframes, but it does not explicitly state that the operation is read-only or describe potential side effects (e.g., whether it modifies the page or returns an empty list). The verb 'list' implies a safe read, but more explicit behavioral disclosure would be helpful.

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 two sentences, highly concise and front-loaded. The first sentence states the core functionality and output fields; the second gives usage context and a pointer to a sibling tool. Every sentence earns its place with no redundancy.

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 zero-parameter, no-output-schema tool, the description is complete: it specifies what is returned (frames with url/name/isMain, plus active frame), the use case (discovering cross-origin iframes), and a transition to the relevant sibling tool (switchFrame). No significant gaps remain for an agent to know when and how to invoke this tool.

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 tool has zero parameters, so the baseline is 4. The description adds no parameter-specific detail because none exist, and the schema is empty, leaving no ambiguity. It fully covers the minimal parameter semantics needed.

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 clearly states the tool lists all frames (main and iframes) on the current page with specific fields (url/name/isMain) and includes the active frame. The verb 'List' and resource 'frames' are specific, and the mention of 'then switchFrame into one' distinguishes it from the sibling tool switchFrame.

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 provides an explicit use case: 'Use to discover cross-origin iframes (e.g. app.example.com), then switchFrame into one.' It also implicitly names the alternative (switchFrame) and the scenario where this tool is appropriate, making the usage context clear.

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