add_modifier

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

Annotations only declare readOnlyHint=false and openWorldHint=false, so the description must carry the rest and does not. It does not say that this mutates the timeline, how it interacts with expectedRevision (concurrency conflict behavior) or requestId (idempotency), or what happens when a modifier of the same type already exists on the target.

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 sentence, front-loaded with the verb and resource, so there is no padding. However, most of its length is a bare enumeration of type names that adds little beyond a vocabulary list and no structure for the required parameters.

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?

A mutating tool with six parameters, a nested object, zero schema descriptions, and no output schema needs materially more than a type list. An agent cannot construct a valid 'modifier' payload or know the format of 'target' from this definition alone.

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% across six parameters, three of them required, and the description only hints at the allowed values of the nested 'modifier' object. It never explains what 'target' refers to (track id? layer id? path?), what keys the modifier object requires, or what expectedRevision/sessionId/requestId are for.

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 ('Add a track modifier') and enumerates the accepted modifier kinds, so the agent knows this creates a modifier on a track. It does not distinguish itself from nearby siblings such as add_parameter, add_binding, or update_track, leaving ambiguity about which construct applies.

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?

No guidance on when to use this versus add_parameter, add_binding, or update_track, and no prerequisites such as whether the track must already exist or whether a session/timeline must be loaded. The only implicit cue is that a timelineId is required.

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