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

Annotations declare a destructive, idempotent, non-read-only mutation, and the description goes well beyond them: it discloses that the call spends the user's Deepnia credits, persists the result to their account, is refunded on failure, and that repeated calls with the same quote_id will not double-charge. That billing/refund/no-double-charge context is exactly the behavior an agent needs before invoking a paid mutation.

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?

Front-loaded with the trigger condition and every clause carries information (payment, persistence, refund, idempotency, next step). However, it is packed into one run-on sentence that could be broken for faster scanning.

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?

An output schema exists, so return values need no explanation, and the description covers the preconditions, cost behavior, failure handling, and the required next call. Nothing an agent needs in order to invoke this paid mutation correctly is missing.

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% and both parameters already document that quote_id comes from quote_video and credits is the accepted price, so the description largely repeats structured data. It adds only a light reinforcement that credits are drawn from the user's Deepnia balance. Baseline 3 is appropriate when the schema does the heavy lifting.

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 a specific verb and resource ("makes the video with Deepnia from that quote_id and credits") and immediately disambiguates from the sibling quote tools by framing it as the post-acceptance step. An agent can tell this apart from create_image/create_voiceover without opening either schema.

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?

Gives an explicit trigger condition ("when the user accepted the price from quote_video"), names the prerequisite tool, and names the required follow-up (get_creation). Usage is fully determined with no inference needed.

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