pane_new

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

Describes making the pane active and optional URL navigation. No annotation contradiction; openWorldHint and idempotentHint are consistent. Adds value 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 clear, front-loaded sentences with no waste. Every sentence adds value: main action, optionality, sibling guidance.

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?

Complete for a simple creation tool: covers purpose, parameter, scope (Cockpit), and sibling references. No output schema needed.

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% with good parameter description; tool description repeats the optional URL behavior, adding little new information. Baseline 3 is appropriate.

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?

Clearly states action: 'Open a new browser pane and make it active'. Distinguishes from siblings by mentioning pane_select and pane_close.

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 tells when to use (open new pane) and when not (use pane_select to switch, pane_close to close). Also notes 'Cockpit only' for context.

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