pane_set_layout

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

Annotations already declare non-readOnly, non-destructive, non-idempotent, openWorld. The description adds real behavioral context: the operation verifies displayed pane count and retained hidden widgets do not count, which clarifies what 'success' means. It does not disclose what happens to existing charts/widgets in panes that no longer exist after a layout change — a material omission for a non-idempotent layout mutation.

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?

A single front-loaded sentence with no filler, and the verification caveat is attached via semicolon rather than padding. Slightly dense but every clause carries information.

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?

No output schema, and the description does indicate the call verifies visible pane count, which partially covers the return. Missing are the fate of panes/widgets not represented in the new layout and any failure-mode behavior beyond the expected_layout_id guard already documented in the schema.

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 50%: target_id and expected_layout_id carry descriptions (the guard behavior is documented there), but 'layout' — an 18-value enum of non-obvious codes like '2-1', '3s', '4h' — and timeout_ms are undocumented. The description's 'native multi-chart layout' framing does not explain the enum vocabulary or the timeout, so it only partially compensates.

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+resource: select a native multi-chart layout, plus the verification of pane count. An agent can distinguish this from pane_layout_options (option discovery) and layout_open (saved layout restore) even though the siblings are not named.

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 verb 'select' — the agent can infer this is the tool for changing pane arrangement. There is no explicit statement of when to prefer it over layout_open or pane_layout_options, and no prerequisites given.

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