list_targetsRetrieve IDs, types, titles, and URLs of debuggable targets—pages, webviews, and Electron windows—to get the target ID needed for subsequent DevTools operations.
List the debuggable targets on the DevTools endpoint — pages, webviews and Electron windows — with their id, type, title and URL. Start here to find the target id every other tool needs.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds concrete return fields and positions the tool as the necessary first lookup, which goes beyond the annotation metadata. No contradictions.
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?
Two efficient sentences: the first gives the resource and output, the second gives workflow guidance. Front-loaded, no filler, every sentence earns its place.
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?
Even though there is no output schema, the description explicitly names the fields returned and explains why the tool matters. For a parameterless list operation, this is complete and self-sufficient.
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 there is no argument semantics to clarify. The schema coverage is trivially 100%, and the description appropriately focuses on the output shape rather than non-existent inputs.
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 ('List'), the resource ('debuggable targets on the DevTools endpoint'), and enumerates the target categories and returned fields (id, type, title, URL). It is immediately distinguishable from sibling tools like screenshot or console_logs.
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 explicitly instructs the agent to 'Start here' and explains that the returned target id is what every other tool needs, providing a clear workflow directive. It doesn't mention when not to use it, but for a listing tool that is not a significant gap.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.