Fan-out send and capture

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

No annotations are provided, so the description must carry the transparency burden. It discloses the core fan-out behavior and optional capture, but it does not mention the tail/pattern modes, per-target delay overrides, or default capture line counts. These are meaningful behavioral traits not obvious from the schema alone, leaving the description somewhat thin.

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?

The description is a single sentence that is immediately informative and free of filler. It front-loads the core action and scope, making it easy to scan alongside sibling tools and understand the tool's purpose at a glance.

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 an 11-parameter tool with no output schema, this description gives only the core action. It omits any mention of the three execution modes (send_capture, tail, pattern) that are central to the tool's range of behavior, so an agent could easily underestimate its capabilities despite the detailed schema. The schema covers parameters well, but the description alone is not fully complete for a tool this complex.

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?

The input schema covers 100% of parameters with descriptions, so the baseline is 3. The description adds no parameter-level meaning beyond the phrase 'optionally capture results,' which simply echoes the capture flag. It does not clarify mode behavior, delay semantics, or target structure beyond what the schema already 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 uses a specific verb ('Send') and clearly identifies the resource: the same keys sent to multiple targets across hosts, with optional capture. This distinguishes it from single-target tmux_send_keys and capture-only tools, and the phrase 'multiple targets (across hosts)' makes its scope unmistakable.

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 phrase 'Send the same keys to multiple targets (across hosts)' gives clear context for when to use this tool: whenever fan-out to multiple panes/hosts is needed. It does not explicitly name alternatives or exclusions, but the primary use case is unambiguous. The optional capture clause further clarifies when it should be chosen over a send-only tool.

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