List debugger sessions

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

With no annotations, the description carries the safety burden and does so: it declares the operation read-only and explicitly states it does not renew any lease, a key behavioral trait given the sibling renew/recover tools. It also previews the returned fields, though it omits any limits, pagination, or permission requirements.

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 tight sentences, front-loaded with the purpose before the read-only caveat. The enumerated output fields make the first sentence dense but nothing is wasted.

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 read-only, 2-parameter listing tool with no output schema, the description compensates by describing the projected return fields and the non-renewing behavior. The main remaining gap is pagination/volume behavior, which is minor here.

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 tabId and browser are already fully documented, including browser's guidance to use browser_list_instances. The description only loosely echoes this via 'in one browser' and 'tab debugger attachments', adding little beyond the schema.

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 (List) and resource (Raw CDP and network sessions holding tab debugger attachments), and enumerates what it surfaces: owner label, lease expiry, in-flight commands, and network projections. This clearly distinguishes it from mutating siblings like browser_debugger_renew, though it never names those siblings explicitly.

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?

Usage is only implied by the purpose ('List ... sessions'). The caveat 'it does not renew any lease' hints at a boundary with browser_debugger_renew, but there is no explicit when-to-use / when-not guidance or named alternative, leaving the agent to infer selection.

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