touch

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

Annotations provide destructiveHint: true. The description adds that it modifies filesystem metadata and creates files, and returns JSON. It does not contradict annotations and provides useful context beyond annotations, though it doesn't detail all behavioral nuances (e.g., idempotency).

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 concise: two sentences with core action, followed by usage guidelines. It is front-loaded with the primary function, and every sentence adds 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?

Given the tool complexity (3 parameters, no output schema), the description covers purpose, side effects, return value, and alternatives. It is complete enough for an AI agent to select and use the tool correctly.

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%, so schema already documents parameters. The description does not add significant extra meaning beyond the schema; it mentions 'dry_run' and 'parents' implicitly in usage context but doesn't elaborate on them. 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 clearly states the tool updates file timestamps or creates empty files if they don't exist. It uses specific verbs (update/create) and resources (file timestamps/files). It distinguishes itself from siblings 'mkdir' and 'truncate' by explicitly stating what it does not do.

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 explicitly states when to use ('refresh timestamps or ensure a file exists') and when not to use ('Not for creating directories – use mkdir. Not for changing file size – use truncate'), with clear alternatives.

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