session_split

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

No annotations are provided, so the description carries the full burden and largely does so: it discloses that the new session is logged from its first byte, that shell integration yields exact exit statuses by default, and that both panes are addressed by session name with typing never following the active pane. It still omits failure modes (e.g., behavior when the session is missing) and 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?

Purpose and differentiation are front-loaded in the opening clause, and the remaining sentences each add distinct value (the tmux comparison, the concrete use case, the addressing rule) without restating structured fields. Size is appropriate for a 7-parameter 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?

An output schema exists, so return values need not be explained, and the description covers the key behavioral traits an agent needs (logging, shell integration, addressing). It is slightly short on error behavior and on routing versus the sibling session_create.

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 every parameter is already documented in the schema, making a baseline of 3 appropriate. The description adds only the general framing of pane addressing and does not clarify parameter syntax or interactions beyond what the schema provides.

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 (split) and resource (a session's window) and explains the resulting artifact: a new pane shown beside the original plus a session of its own. It clearly distinguishes itself from raw `tmux split-window`, but does not explicitly differentiate from siblings like session_create, which also creates sessions.

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?

It gives a clear when-to-use ('Use it instead of typing `tmux split-window`, whose pane has neither [logging nor shell integration]') and an illustrative scenario ('a testsuite running in one pane, gdb in the other'). What is missing is explicit when-not guidance relative to the sibling tool session_create.

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