write

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

The annotation destructiveHint: true indicates the tool can destructively modify files, and the description does not contradict this. However, the description adds no behavioral traits beyond the annotation—it does not mention overwrite behavior, file creation, directory handling, or any side effects. The phrase 'Write or append' merely restates the core function.

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 a single, efficient sentence that is front-loaded with the action and target. There is no redundant wording or filler. It earns its place by clearly stating the tool's purpose without wasting tokens.

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 rich schema and destructiveHint annotation, the description covers the basic purpose but leaves out behavioral nuances such as the effect of different modes, frontmatter handling, or return values. However, since the schema fills the parameter details and the annotation warns about destructiveness, the description is minimally adequate but not thorough.

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 provides 100% coverage with descriptions for all four parameters (path, content, mode, frontmatter), including the enum and default for mode. The description adds no extra parameter semantics, so the baseline of 3 applies.

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's function with a specific verb ('Write or append') and resource ('file in the AI knowledge vault'). It distinguishes itself from the sibling 'read' tool and other non-file tools, making its purpose immediately clear.

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 provides no guidance on when to use this tool versus alternatives. It does not mention any exclusions, prerequisites, or comparison to other write-related operations. The only context is the vault location, which is insufficient for decision-making.

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