Show or hide a source

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

Annotations only indicate non-read-only and non-destructive behavior. The description adds valuable context: toggle behavior via omitted 'visible', dual canvas application, cross-scene source resolution, and return of the new state. This goes beyond the minimal annotation coverage.

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?

Three concise sentences with no filler. The description is front-loaded with the primary action, and every sentence contributes unique information about behavior, defaults, or edge cases.

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 visibility toggle with no output schema, the description fully covers behavior, defaults, cross-scene resolution, and return value. No significant gaps remain, making it complete for an AI agent to select and invoke correctly.

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%, but the description enriches parameter meaning: clarifies toggle via omitted 'visible', the 'format' parameter's effect on canvas scope, and source_id resolution across scenes. This adds edge-case guidance not evident from the schema alone.

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 tool shows, hides, or toggles a source in a scene, using a specific verb and resource. It distinguishes itself from sibling tools like set_source_transform or set_source_mute by focusing solely on visibility.

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: use this when you need to show/hide/toggle a source, with notes on canvas scope and cross-scene resolution. It does not name alternatives explicitly, but the context is clear enough for selection.

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