macos_pick_file

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

With no annotations provided, the description carries full burden. It discloses key behavioral traits: the tool opens a dialog (implying user interaction), returns a file path or null if cancelled, and is read-only (no mutation implied). However, it doesn't mention platform-specific constraints (macOS-only), permissions needed, or error handling beyond cancellation.

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, zero waste. The first sentence states the core purpose and outcome, the second covers the cancellation case. It's front-loaded with essential information and appropriately sized for a simple tool.

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's low complexity (interactive file picker), 100% schema coverage, and no output schema, the description is mostly complete. It covers purpose, behavior, and edge cases (cancellation). However, it could benefit from mentioning macOS-specific context or integration with sibling tools for a perfect score.

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 100%, so the schema fully documents all three parameters. The description adds no additional parameter semantics beyond what's in the schema (e.g., no examples or constraints). Baseline 3 is appropriate when the schema does the heavy lifting.

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 ('Open a file picker dialog') and outcome ('return the selected file path'), distinguishing it from sibling tools like macos_pick_files (multiple files) and macos_pick_folder (folder selection). It uses precise verbs and specifies the resource (file path).

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 implies usage context (interactive file selection) and distinguishes from macos_pick_files and macos_pick_folder by specifying single file selection. However, it lacks explicit guidance on when to use this versus alternatives like macos_get_finder_selection or macos_save_dialog, which would require more detailed comparison.

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