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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so safety and side-effect-free behavior are covered by structured data. The description adds real value beyond that: the pricing formula (sum of narration speech cost plus a flat 10-credit assembly fee) and that it is a free preview, which is not in any annotation.

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 short sentences, front-loaded with the tool's identity as a free preview, then the pricing mechanics, then the usage context. No sentence is wasted.

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 the description needn't explain return values. It supplies the pricing formula and the free-preview framing, which are the key pieces an agent needs to decide to call it before assemble_demo_video. It could be slightly more complete by hinting at what the segment array expects, but nothing critical 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?

Parameter count is 1 and schema description coverage is 0%, meaning the nested segment properties (voiceId, audioUrl, videoUrl, narrationText, etc.) are undocumented anywhere. The description mentions segments in prose but does not explain the fields, so the schema's structure carries most of the burden; baseline 3 is appropriate for a single top-level parameter.

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 (quote) and resource (credit cost of a multi-segment demo video) and explicitly names the sibling tool it previews (assemble_demo_video pricing). An agent can distinguish this dry-run costing tool from quote_voiceover and quote_test_card 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?

Explains when to use it ('Useful before committing to a longer video') and names assemble_demo_video as the paid alternative. It gives clear context but stops short of stating explicit exclusions or prerequisite conditions for the quote itself.

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