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

Annotations already indicate this is not read-only and not destructive. The description adds the behavioral scope of renaming and reparenting a folder, but it does not disclose side effects like how moving a folder impacts paths or whether the operation is idempotent. This is adequate but not rich.

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 primary action and key parameters are front-loaded, and the alternative tool is mentioned only after the main capability is established. Every sentence 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 update tool with one required parameter, full schema coverage, and annotations, the description is largely complete. It identifies what the tool does, how it differs from create_folder, and the relevant fields. However, there is no output schema, and the description does not mention what the tool returns or whether it confirms success, which leaves a small gap.

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 already fully documents id, name, and parentid. The description adds operational context by describing name as 'rename' and parentid as 'change its parent', but it does not add meaning beyond that. Baseline 3 is appropriate.

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 and resource: 'Update a file folder by id', and clarifies the two concrete operations: rename it or change its parent. It also explicitly distinguishes itself from the sibling create_folder, leaving no ambiguity about what this tool does.

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 gives an explicit when-not condition and names the alternative: 'To create a brand-new folder use create_folder instead.' This clearly routes an agent to the correct tool and covers the main competing operation.

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