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

Annotations already declare readOnlyHint/idempotentHint/non-destructive, so safety is covered. The description adds traits the annotations do not: signed previews get refreshed on read, polling should be bounded, and access requires authorization. That is meaningful behavioral context beyond the structured 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 front-loaded sentences with little waste; purpose comes first, then behavioral notes, then sibling routing. 'Complete means the editable timeline is assembled' is compact but slightly cryptic without the surrounding context.

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-value detail is not required here. The description still covers scope, authorization, polling, and hand-off to export tools, which is nearly everything an agent needs to invoke a simple read correctly; only parameter-level detail is thin.

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 only 33% (projectId has a bare 'UUID string.', revisionId none at all), and the description does not compensate by explaining the identifiers. They are self-explanatory UUIDs and the phrase 'authorized storyboard revision' loosely frames revisionId, but the nullable/defaulted workspaceId is never addressed.

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 ('Read one authorized storyboard revision') and enumerates what the response covers (scene and reference previews, estimate, approvals). It also distinguishes itself from the write siblings and explicitly routes downloadable-output needs to exports_start/exports_list.

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 clear context for use: reading a single authorized revision and polling it until the editable timeline is assembled, with exports_start/exports_list named as the alternative for MP4 output. It lacks explicit when-not-to-use guidance versus siblings like video_storyboard_create/revise, but the alternative routing is concrete.

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