Generate video

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

Discloses key behavioral traits: uses user's own API keys, switches between Gemini Veo and mock, and is expensive with real keys. This goes beyond the schema and annotations (none provided), adding operational context.

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, front-loaded with the core purpose and followed by a critical warning. No redundancy or vague filler.

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?

Covers the most important behavioral context (provider, cost) but omits parameter details and return/output expectations. For a 4-param tool with no output schema, the description is too sparse to fully guide an agent.

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 only 25% (provider), and the description does not explain prompt, aspect, or durationSec. The description mentions 'short video clip' but provides no param-specific meaning, leaving the agent to guess.

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?

States exactly what the tool does: 'Generate a short video clip'. The mention of 'Gemini Veo' and 'mock' differentiates it from siblings like render_video and generate_image, showing a specific AI-generated video use case.

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?

Provides clear usage context: 'only call when the user’s workflow needs generated footage' and warns about cost with real keys. This gives an explicit condition for use and a caution, though it doesn't name alternative tools directly.

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