Create (plan + generate, budget-capped)

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

Discloses key behaviors: auto-selects media type, tier, aspect ratio, duration; budget cap with safe failure; different result types (URL vs job id); no billing for failed generations. Annotations are consistent, no contradictions.

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 sentences, front-loaded with purpose. No unnecessary words, but could be slightly more structured with bullet points for clarity. Efficient overall.

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 main functionality, parameters, conditional behavior, and output types. Existence of output schema fills in return details. Minor gap: no mention of error handling beyond cost refusal.

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 covers both parameters with descriptions. The tool description adds behavioral context: intent as natural language, max_cost_cents as spend ceiling with refusal behavior. Enhances understanding beyond schema.

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 combines planning and generation for image/video, with the 'zero decisions' path. It distinguishes from siblings like generate_image, generate_video, and plan by being the unified, automated option.

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?

Explicitly says when to use (plain language, zero decisions) and the mandatory max_cost_cents parameter. It explains what happens if cost exceeds ceiling, but doesn't explicitly state when not to use (e.g., for specific media type choices).

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