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

No annotations exist, so the description carries the full behavioral burden. It discloses copy semantics (self-contained, fresh ids, detached, source changes don't affect the copy), group-children inclusion, byte copying, live editor pickup, and return shape, all beyond what schema provides.

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 dense but efficient description; every clause earns its place. It front-loads the core purpose, then covers usage, prerequisites, runtime behavior, and return value without 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 three-parameter operation with no output schema and no annotations, the description is essentially complete. It specifies required inputs, source/destination semantics, prerequisites, behavioral effects, and the return contract, leaving little an agent needs to infer.

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 covers 100% of parameters already, so baseline is 3. The description adds value by explaining the relationship between sourceProjectId and elementId ('from list_collection') and the consequence of those parameters (fresh ids, original position, full detachment). This lifts it slightly above baseline.

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 ('Add'), resource ('item from the user's Collection into a project'), and copy semantics. The direction (from collection to project) clearly distinguishes it from sibling tools like add_to_collection and add_image_layer, so an agent can select it without opening schemas.

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?

Gives clear context: it is the tool for copying an existing collection item into a project, with parameters sourced from list_collection. It states prerequisites (element must be in source collection, read access required) but does not explicitly name when to prefer an alternative like add_to_collection, so it stops short of a 5.

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