remotion_add_lower_third

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes that this tool creates an overlay that appears at a specific time and duration, doesn't affect the main timeline, and returns JSON with component info. It covers key behavioral aspects like timing, non-destructive overlay nature, and output format, though it could mention potential side effects or error conditions.

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 well-structured and appropriately sized. It begins with a clear purpose statement, provides essential context about overlays, lists parameters with explanations, describes the return value, and includes a practical example. Every sentence adds value without redundancy.

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 moderate complexity (6 parameters, no output schema, no annotations), the description provides strong contextual completeness. It explains what the tool does, how parameters work, and what to expect in return. The main gap is the lack of explicit error handling or permission requirements, but overall it's quite comprehensive for this type of overlay creation tool.

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 provides excellent parameter semantics beyond the schema. While schema description coverage is 0%, the description clearly explains each parameter's purpose: 'name' as main text, 'title' as optional subtitle, 'start_time' as when to show, 'duration' as how long to show with default, 'variant' as style options, and 'position' as screen placement. This fully compensates for the lack of schema descriptions.

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's purpose: 'Add a lower third overlay to the composition' with specific details about creating a 'name plate overlay (TV-style graphics)' that appears at a specific time. It distinguishes this from sibling tools like remotion_add_title_scene by focusing on overlay creation rather than scene or project management.

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 by stating 'Lower thirds are overlays and don't affect the main timeline,' which helps differentiate from timeline-altering tools. However, it doesn't explicitly state when to use this tool versus alternatives like remotion_add_title_scene or provide clear exclusions for when not to use it.

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