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

Far exceeds the annotations: it discloses the two-step quote/approve flow, that nothing is debited on step 1, that step 2 deducts coins and starts finalization, the 7-day expiry, and the idempotency guarantee ('Repeating the call for the same draft result never charges twice'), which reinforces the idempotentHint. Annotations only flag destructive/idempotent/non-readOnly; the description explains the actual cost and approval mechanics.

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-loads 'PAID ACTION in two steps' and then walks through step 1 and step 2 in order, matching the call sequence. It is dense but nearly every clause carries operational weight; the single unused detail is the unexplained output_format.

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 7-parameter, no-output-schema, destructive mutation tool, the description covers the charging model, approval requirement, and follow-up tool. The only meaningful omission is output_format semantics, which neither the schema nor the description explains.

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?

With only 14% schema coverage, the description does substantial work: it ties request_id to the draft returned by aimixer_submit/aimixer_status, explains result_index selects among multiple results, and enumerates the step-2 fields (quote_confirmation, pricing_revision, expected_price, approval_handle) and their roles. It omits any explanation of output_format (mp4/mov), leaving a real gap.

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 ('finalize a finished Seedance 2.5 Draft to a 1080p video') and explicitly contrasts it with generating from scratch. It also disambiguates from siblings by naming aimixer_submit and aimixer_status as the draft origin and follow-up tools.

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 explicit preconditions (draft must be a cheap 480p preview, finalized within 7 days of creation) and exclusions ('Other models and generations are not drafts'). It clearly separates step 1 (quote) from step 2 (confirm) and states when each is appropriate.

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