vault_append

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses a non-obvious output format ('Paths in this tool's output are formatted as markdown links...') and a precondition ('heading is required and must exist in the file'). This adds significant context beyond a simple append operation. However, it omits error behavior (e.g., file not found) and permission details, though a 4 is justified given the specific behaviors shared.

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 three sentences, each with a distinct purpose: the first states the core action and its optional heading feature, the second explains the output path formatting, and the third gives a practical instruction for relaying paths. No filler or redundancy; the most important information is front-loaded.

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 tool with 4 parameters, no output schema, and no annotations, the description covers the core append action, the position/heading dependency, and a key output-format behavior that affects how results should be interpreted. It stops short of describing error handling or the exact return format, but these are not critical for selecting or invoking the tool. The description feels sufficient for an agent to 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?

The schema already provides descriptions for all 4 parameters (100% coverage), so the baseline is 3. The description adds meaningful semantic value by clarifying the relationship between heading and position ('When 'position' is specified, heading is required and must exist in the file') and by noting how paths should be handled ('pass only the bracket text... never the full markdown link'). This goes beyond the schema's individual parameter descriptions.

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 begins with a specific verb+resource combination: 'Append content to an existing file', which clearly distinguishes it from sibling tools like vault_write (creation) and vault_edit (modification). It also adds a distinguishing feature: 'optionally under a specific heading', making the tool's unique purpose and scope 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 implies usage for existing files ('Append content to an existing file') but does not explicitly state when to prefer this over alternatives. It does provide a clear constraint for position usage ('When 'position' is specified, heading is required and must exist in the file'), but this is a parameter rule, not tool-selection guidance. No explicit exclusions or alternative references are given.

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