build_motion_timeline

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds the useful disclosure that output is expressed in three forms (seconds, frame ranges, normalized progress), which partially compensates for the absent output schema, but it says nothing about determinism, rounding, or how fps affects the result.

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?

A single dense sentence with no filler, front-loading the action and the output forms. Nothing is wasted, though the terseness is the root of the ambiguity noted 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?

For a tool with a nested beats array, three constrained numeric parameters, no output schema, and zero schema descriptions, the description is far too thin. It gestures at output shape but omits duration/fps semantics and the relationship between weights and allocated time.

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 0%, so the description carries the full burden for three parameters. It references 'weighted beats' (mapping loosely to the beats array and weight field), but never explains duration, fps (its default of 30, range 12-120), or the 1-24 beat limit and 100 weight cap enforced by 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?

States a specific verb (allocate) and resource (weighted beats) and names the resulting artifacts (seconds, frame ranges, normalized progress). It reads as a distinct build operation versus siblings like validate_motion_spec or build_reduced_motion_plan, though it never explicitly names the timeline object or contrasts with those siblings.

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 when-to-use guidance, no prerequisites, and no mention of alternatives such as validate_motion_spec or build_reduced_motion_plan. The agent must infer the workflow position of this tool entirely from its name and the sibling list.

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