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

The description restates idempotency in a slightly more detailed way ('succeeds without creating duplicates'), which adds a nuance beyond the idempotentHint annotation. However, it does not disclose other behavioral aspects like failure modes (e.g., invalid path) or whether parent folders are auto-created. Given that annotations cover safety (non-destructive, not read-only), the description fits within expectations.

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?

Two sentences with no filler. The first sentence states the core purpose, the second gives usage and idempotency. It is front-loaded and each clause 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?

For a simple creation tool, the description covers purpose, usage, and idempotency. Parameters are fully documented in the schema, and the output schema (not shown) likely describes the return. It does not mention error handling or permissions, but those are not critical for a straightforward folder creation action when annotations indicate non-destructive behavior.

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?

The input schema already provides 100% coverage, including clear examples for 'folder' and a detailed explanation for 'vault_id'. The description adds no parameter-specific information, so it relies on the schema as the baseline. The description's mention of scaffolding does not elaborate on parameter usage.

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 ('Create') and resource ('explicit empty folder in the personal knowledge base'), clearly distinguishing it from siblings like create_note or delete_folder. It also implies a scoping restriction ('explicit') that sets it apart from tools that might auto-create parents.

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?

It explicitly says 'Use to scaffold folder structure before placing notes,' giving a clear when-to-use context. It does not explicitly name alternatives, but the phrase 'before placing notes' implies it is for folder creation prior to note writing, which is sufficient guidance in a small toolset.

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