list_all_tabs

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

Annotations already cover readOnlyHint, openWorldHint, idempotentHint, and destructiveHint. The description adds meaningful behavioral context: chrome-extension pages cannot become sessions, have no session id, and require cdp_command. It also notes the tool works with no tabs open, covering an edge case beyond annotations.

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?

Three sentences, each carrying distinct information: the listing scope, the chrome-extension caveat, and the empty state. The key differentiator is front-loaded and there is no filler.

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?

Given the read-only nature, strong annotations, and an output schema, the description covers the key behavioral distinctions and edge case. The only minor gap is the unexplained session_id parameter, but it is optional and not central to using the tool 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?

Schema coverage is 0% and the description doesn't explain the optional session_id parameter. However, the parameter is optional and defaulted to null, making it less critical. Still, the description adds no semantic meaning for the parameter, so baseline 3 applies.

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 a specific verb and resource: 'List every open tab', and immediately differentiates from sibling list_tabs by noting it includes chrome-extension:// pages that list_tabs hides. This lets an agent distinguish the tools without inspecting schemas.

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?

Explicitly names list_tabs as the alternative and explains the distinguishing condition: chrome-extension pages. It also provides actionable routing guidance by telling the agent to drive those tabs with cdp_command(tab_id=...) since they have no session id.

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