apply_manual_keyframe_track

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

Annotations only provide readOnlyHint=false and destructiveHint=false. The description adds meaningful behavioral context: it replaces any existing track on the field, returns `{ ok, nodeId }`, and notes the beta and Figma-Design-only restrictions. This exceeds what annotations reveal, though it could more prominently state the replacement side-effect.

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 well-structured sentences: purpose with examples, parameter walkthrough, and behavioral/return/platform note. Every sentence adds value and there is no redundancy.

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 complex tool with nested objects and no output schema, the description covers the return shape, replacement semantics, and platform/beta caveats. It lacks error/edge-case guidance, but the rich schema and sibling context make it reasonably complete.

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%, with every parameter and nested property already described in the schema. The description's summary of `field` and `track` restates schema content without adding new meaning, so the baseline of 3 applies.

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 description opens with a specific verb ('Set'), a clear resource ('hand-authored Figma Motion keyframe track'), and scope ('on a node for one field'), followed by concrete field examples. This makes the tool's purpose unambiguous and distinguishes it from siblings like `remove_manual_keyframe_track` and `apply_animation_style`.

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?

The description implies usage scenarios through phrases like 'hand-authored' and 'Replaces any existing track on that field,' but it never explicitly says when to use this tool instead of `apply_animation_style` or when not to use it. The beta/Design-only note is a constraint, not a comparative guideline.

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