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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description adds real behavioral content: voiceover lines are explicitly drafts to be polished, and a hard constraint 'never add claims or results the user didn't provide' guards against fabrication. It also discloses the shape of what gets produced. It doesn't disclose that the call seeds durable conversation state (implied only by schema fields).

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, zero filler, with the output structure front-loaded and the two most actionable rules (polish voiceover, never invent claims) placed last for emphasis. Every sentence carries distinct information.

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?

With 15 parameters and no output schema, the description usefully compensates by enumerating the return structure section by section, and it states the non-negotiable constraint. Minor gaps: no mention of the platform/format defaults that shape the script, and no note on the conversation_id/uid continuity that the schema treats as significant.

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 87%, so the schema already carries parameter meaning; description text adds no syntax, defaults, or format guidance beyond the implicit link between output sections and the cta/tone/concept inputs. Baseline 3 applies 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?

Specific verb ('Draft') plus a precisely enumerated deliverable: hook with timing, body scenes with time ranges, shot directions, voiceover, on-screen text, CTA, caption, hashtags. That distinguishes it clearly from research/analysis siblings, but no sibling is named, so the contrast with ideate_ugc_content (referenced only inside the schema) is left implicit.

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: the agent can infer this is the downstream step after concept generation, and the schema's concept description ('an idea title from ideate_ugc_content') hints at the chain. However, the description itself never says when to use this versus ideating or running the UGC agent, and gives no prerequisites or exclusions.

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