render_previews

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

With no annotations, the description carries the full burden. It does not disclose whether this is a long-running/blocking render, whether existing preview files are replaced, whether it mutates project media, or what it returns — all important for an operation named 'render'.

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?

One short, front-loaded sentence with no filler. It is arguably under-specified rather than padded, which costs nothing in conciseness but leaves gaps elsewhere.

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?

No annotations and no output schema, so everything an agent needs — prerequisites, blocking behavior, side effects on existing previews, return shape — had to come from the description, and almost none of it is there. Inadequate for a render/mutation-style operation.

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?

The single optional param has 0% schema coverage, but the description glosses the enum as 'in to out, or all', which does add meaning beyond the bare enum values. It still omits the default when 'range' is omitted, which matters for a 0-required-param tool.

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?

The verb+resource pair 'Render timeline previews' is concrete, but 'previews' is ambiguous in a tool set that already contains export_sequence, export_frame, and export_audio; the description never says how a preview differs from an export. The parenthetical clarifies the range options but not what is being produced.

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?

There is no statement of when to use this instead of export_sequence, export_frame, or queue_export, nor any prerequisites (active sequence required? existing preview files overwritten?). The agent must guess at routing among many sibling export/render tools.

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