3D-MCP

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

No annotations are provided, so the description carries full burden. It states 'Update multiple Channels' which implies a mutation operation, but doesn't disclose critical behavioral traits: whether this requires specific permissions, if changes are reversible, what happens on partial failures, or rate limits. For a batch mutation tool with zero annotation coverage, this is a significant gap in transparency.

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?

The description is a single, efficient sentence with zero waste—'Update multiple Channels in a single operation' is front-loaded and appropriately sized. It conveys the core purpose without unnecessary elaboration, earning full marks for conciseness.

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?

Given the tool's complexity (batch mutation of animation channels with a nested parameter structure), lack of annotations, and no output schema, the description is incomplete. It doesn't explain what 'Channels' are, the scope of updates (e.g., can it modify all properties?), error handling, or expected outcomes. For a tool with rich input schema but no other structured data, more context is needed.

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 fully documents the single parameter ('items') and its nested properties. The description adds no parameter semantics beyond what's in the schema—it doesn't explain the structure of 'items', provide examples, or clarify relationships between fields like 'clipId' and 'ids'. Baseline 3 is appropriate when the schema does all the heavy lifting.

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 'Update multiple Channels in a single operation' clearly states the verb ('Update') and resource ('Channels'), and specifies it handles multiple items. However, it doesn't distinguish this from sibling tools like 'updateKeyframes' or 'updateClips'—it's vague about what 'Channels' are in this context (animation channels based on schema) and how this differs from other update operations.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., existing channels to update), compare it to single-channel updates (if any), or specify scenarios where batch updating is preferred over individual operations. With many sibling tools including 'createChannels' and 'deleteChannels', the lack of context leaves the agent guessing.

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