Estimate the credit cost of a CraftStory 2.0 video

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

With no annotations, the description carries the full burden and does disclose key behavior: it is side-effect-free ('without creating anything') and it exposes the exact pricing rules, including per-second rates, the empty-lipsync discount, per-job rounding, and the MiniMax H3 flat rate. It does not state the return shape (a scalar credit total), which is the main remaining gap.

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 core purpose, then a dense but relevant rate breakdown; every sentence earns its place. The opening clause is slightly ungrammatical ('Credits a craftstory-2 job would cost'), costing a point.

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 pricing tool with no annotations and no output schema, the description explains the cost model thoroughly enough to predict the result. It falls short only on the unexplained sync_so mode and on not stating what the returned value looks like.

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 0%, so the description must compensate, and it partially does by tying resolution values (480p/720p) and lipsync_mode=empty to concrete rates. However sync_so is never explained and audio_clip_ids semantics (what counts as a billed second) are left undefined, so the mapping is incomplete.

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: it returns the credit cost a craftstory-2 job would incur for given audio clips and settings. The phrase 'without creating anything' explicitly separates it from the create_* siblings, so an agent can pick the right tool without opening schemas.

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?

Usage is implied rather than stated: 'without creating anything' suggests a pre-flight/dry-run estimate before calling create_craftstory2_video, but it never says when to prefer this over alternatives or that it must precede creation. Nothing is misleading, but the routing is left to inference.

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