send_control_signal

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

With no annotations, the description solely handles transparency. It lists supported signals and notes that SIGINT avoids killing the harness, but does not disclose that SIGQUIT may cause a core dump or other potential side effects. The description is missing behavioral details like authentication needs or error handling, earning a 3.

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?

Two sentences with no superfluous words. The first sentence states the action, and the second lists supported signals. The description is perfectly front-loaded and efficiently uses space.

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 simple one-parameter tool, the description covers the essential aspects: what it does, when to use it, and supported values. It references 'persistent pane (FR-04)' which may be assumed context. An output schema exists, so return values are not required. Minor gaps (e.g., error handling) prevent a 5.

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 has only one parameter with no description (0% coverage). The description adds value by listing supported signal values and explaining their effects (e.g., Ctrl+C for SIGINT). This compensates for the schema gap, though it could include an explicit allowed values list.

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 clearly specifies the action ('issue a control signal keystroke'), the target ('persistent pane (FR-04)'), and provides concrete examples. It distinguishes itself from siblings (execute_command, read_terminal_buffer) by focusing on sending signals rather than executing commands or reading output.

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 provides a clear use case 'break out of a blocking process without killing the harness', implying when to use it. However, it does not explicitly contrast with alternatives or state when not to use it, but the context with sibling tools makes the distinction clear.

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