session_run

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

With no annotations provided, the description carries full burden. It discloses that the tool 'sends text + Enter' (execution behavior) and describes parameter-driven targeting (active vs. specific vs. all sessions). However, it doesn't cover permissions needed, error handling, rate limits, or what happens if a session doesn't exist—important for a command execution tool.

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 front-loaded with the core purpose, followed by a well-structured Args section. Every sentence earns its place by clarifying behavior or parameters, with zero redundant or vague language.

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?

Given 3 parameters with 0% schema coverage and no annotations, the description does an excellent job explaining parameters and basic behavior. However, as a command execution tool with potential side effects, it could benefit from mentioning output handling (though an output schema exists) or error scenarios to be fully complete.

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 0%, so the description must compensate fully. It provides clear semantics for all three parameters: command ('command string to execute'), session_id ('Target session ID. Omit for the active session'), and all_sessions ('If true, run in every session'), adding crucial meaning beyond the bare schema.

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 states the specific action ('Execute a command') and resource ('in an iTerm2 session'), with additional behavioral detail ('sends text + Enter'). It distinguishes from siblings like session_send (which may not send Enter) and session_read (which reads 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 clear context for when to use specific parameters (omit session_id for active session, use all_sessions for every session). However, it lacks explicit guidance on when to choose this tool over alternatives like session_send or batch, or any prerequisites for execution.

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