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

No annotations are supplied, so the description carries the full behavioral burden. It discloses the partial-update semantics, but says nothing about permission/auth requirements, whether clearing values (clipEnd/speedRamp/imageMediaId accept null) is reversible, or the destructive nature of full-list replacement fields like mediaRefs and taggedAssets. For a 22-parameter mutation tool this is a significant 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?

Three short sentences, front-loaded with the action and ending with the most operationally important constraint. The field enumeration is somewhat redundant against a 100%-covered schema, which keeps it just short of a 5.

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 22-parameter mutation tool with no annotations and no output schema, the description is thin: it omits sibling routing, permission requirements, and the replace-not-merge behavior of list fields. The partial-update sentence is the one strong element, but overall an agent would need to open the schema and guess at alternatives.

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 100%, so the schema already documents all 22 parameters, which sets the baseline at 3. The description adds a useful conceptual grouping (scene, order, timing, media refs, dialogue, motion prompt, tagged assets) but omits several parameters entirely (speedRamp, playbackSpeed, linkEndToNextStart, hideStartFrame, volume), so it does not exceed the schema.

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?

Clear verb+resource ('Update an existing shot') followed by an enumeration of the mutable field groups. An agent immediately knows this mutates a shot. However, it never distinguishes itself from siblings that overlap heavily (move_shot_to_scene, reorder_shots, update_shot_media_ref, split_shot), so it falls short of a 5.

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?

'Only provided fields are changed' is a genuine invocation guideline that tells the agent this is a partial/PATCH-style update, so no full read-modify-write is required. But there is no guidance on when to prefer this tool over the scene/reorder/media-ref siblings, so usage is only implied.

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