run_and_capture

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the description need not repeat those. It adds useful context: the tool runs for a specified duration, captures a screenshot, then stops, and requires a display server. This goes beyond the annotations without contradicting them.

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 fluff. The first sentence states the core action and stopping behavior; the second differentiates from siblings and adds the display server prerequisite. Every phrase contributes.

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?

The description, combined with the rich annotations and 100% schema coverage, is fully complete for this tool's complexity. It covers purpose, runtime behavior, prerequisites, and sibling differentiation. No return schema is needed as the tool is screenshot-focused and the output path is in the parameters.

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 coverage is 100%; all parameters already have descriptive comments. The description does not add additional parameter-level meaning beyond what the schema provides (e.g., duration, outputPath, scene). It satisfies the baseline for full schema coverage but offers no extra semantic value.

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 states the action clearly: 'Run the project for a duration, capture a screenshot, then stop.' It also differentiates from siblings by explicitly contrasting with capture_screenshot ('Runs the full game') and game_screenshot ('without needing run_interactive'). This provides a specific verb, resource, and scope.

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 context for when to use this tool vs alternatives: it explicitly states it runs the full game unlike capture_screenshot, and does not require run_interactive unlike game_screenshot. It also notes the prerequisite of a display server. However, it does not explicitly say 'use this instead of X when Y' or provide exclusions beyond these comparisons.

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