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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutating and potentially destructive nature is known. The description adds only the domain of change (mode/ownership) and an example, without disclosing extra behavioral nuances like root privileges for chown, immediate effect, or lockout risk.

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 single, front-loaded sentence that captures the trigger condition, the intended operation, and a concrete example in roughly 20 words. Every phrase earns its place with no fluff.

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?

With 100% schema coverage, an output schema, and annotations covering safety, the description fully handles tool selection context. It does not mention recursive behavior or uid/gid options, but those are fully specified in the schema, so the description need not repeat them.

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 coverage is 100% with each of the 6 parameters described (path, mode, device, recursive, uid, gid). The description just restates the general concept of changing mode/ownership, adding no syntax or format guidance beyond the schema.

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 ('change mode bits or ownership of a file or directory') with a concrete illustrative example ('to make a script executable'). This clearly distinguishes it from sibling file operations like delete_path or write_file.

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 trigger condition: 'Use this when the user asks to change mode bits or ownership.' It lacks explicit when-not-to-use phrasing, but no sibling tool handles permissions, so no exclusions are necessary.

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