session_focus

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the action ('Focus (activate)') which implies a state change, but doesn't describe what happens visually (e.g., brings session to foreground), whether it requires specific permissions, or what happens if the session doesn't exist. The description adds minimal behavioral context beyond the basic action.

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 extremely concise with zero wasted words. The first sentence states the core purpose, followed by a clean 'Args' section for parameter documentation. Every element serves a clear purpose, making it easy to parse quickly.

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 the tool has an output schema (which handles return values), 1 parameter with 0% schema coverage (compensated by description), and no annotations, the description is minimally adequate. However, for a state-changing tool in a complex terminal environment, it lacks important context about behavior, error conditions, and relationships to sibling tools.

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 description includes an 'Args' section that documents the single parameter 'session_id' and its purpose ('The session ID to focus'), providing meaningful semantics. Since schema description coverage is 0% and there's only 1 parameter, this adequately compensates, though it doesn't specify format requirements (e.g., where to obtain session IDs from 'session_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 states the action ('Focus (activate)') and target resource ('a specific iTerm2 session'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'window_focus' or 'app_get_focus', which also deal with focus/activation concepts in the same iTerm2 context.

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?

No guidance is provided about when to use this tool versus alternatives. The description doesn't mention prerequisites (e.g., needing an existing session), exclusions, or comparisons to related tools like 'session_list' (to find session IDs) or 'window_focus' (for window-level activation).

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