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

Beyond annotations (which only set readOnlyHint false, etc.), the description discloses two key behaviors: the copy is placed immediately after the original, and every block receives a new id, making the copy independent in the player. This adds meaningful context about side effects and independence. It does not mention permission requirements or potential impacts on referenced resources, but for a duplication tool the primary behavior is well covered.

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 two sentences with no filler. The core action (copy placement) is front-loaded, and the behavioral note about new ids is relevant and concise. Every word earns its place.

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?

The tool is simple with two required parameters and an output schema (not shown but present). The description covers what the tool does and a key behavioral outcome (independence). It does not mention prerequisites like course existence or validation, but those are implicit in the schema and typical for such operations. For a straightforward duplication tool, it is sufficiently 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?

Both parameters (courseId and screenId) have descriptive schema entries with 100% coverage. The description adds no additional parameter-specific meaning beyond what the schema already provides, so the baseline of 3 applies. It correctly implies the scope (course context and screen within it) but does not elaborate on formats or constraints.

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 states a specific verb ('copies') and resource ('a screen'), and specifies placement ('directly after the original'). It also clarifies that the copy gets new block ids, distinguishing it from simply moving or referencing a screen. This clearly separates it from siblings like add_screen (creates from scratch) or update_screen (modifies existing).

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 when to use it (when you need a duplicate of an existing screen), but it does not explicitly state alternatives or exclusions. There is no mention of 'use this instead of add_screen for copies' or any condition where this tool should not be used. The guidance is implied through the verb and placement but lacks explicit routing.

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