iterm2_split_pane

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 that a new pane is created (mutating action) and states the return value (session ID), which is helpful. However, it doesn't mention whether the original pane remains active, how to determine the new dimensions, or any prerequisites (e.g., iTerm2 must be running).

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?

Single efficient sentence that states purpose, behavior, and return value with no wasted words. It front-loads the core action and mentions the result. Could potentially note caveats but is appropriately concise for the simplicity of the tool.

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 straightforward two-parameter split operation with full schema coverage, the description covers the essentials: purpose, behavior, and return value. The lack of output schema means the description appropriately notes the session ID return. Gaps include no mention of error scenarios (invalid session ID) or whether splitting is synchronous. Adequate but not comprehensive.

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 detailed parameter descriptions. The schema already explains the vertical boolean semantics and the session_id shorthand format thoroughly. The description adds the session ID return value context, which contributes meaning beyond the schema. Description does not need to duplicate what the schema already covers well.

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?

Clear verb+resource+action: splits an iTerm2 pane horizontally or vertically, creating a new pane. It also states the return value (session ID). It distinguishes from siblings like iterm2_send_text and iterm2_list_panes, though it doesn't explicitly differentiate from iterm2_side_pane which sounds similar.

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 implies when to use it (when you need to split a pane), but provides no explicit exclusions or alternatives. There's a sibling named iterm2_side_pane which could be confusingly similar, but the description does not clarify when to choose one over the other.

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