Obsidian MCP Server

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

With no annotations provided, the description carries the full burden. It discloses behavioral traits: it's a read operation (implied by 'List'), returns folder structure with paths and names, and mentions optional directory parameter with default behavior. However, it doesn't specify pagination, rate limits, or error conditions, leaving some gaps.

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 well-structured with clear sections (purpose, when to use, when not to use, returns). Every sentence adds value: the first states the core function, the bullet points provide practical guidance, and the returns section clarifies output. No wasted words.

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 read-only tool with no output schema, the description is mostly complete: it covers purpose, usage guidelines, and output format. However, with no annotations and incomplete parameter documentation (missing 'ctx'), there are minor gaps in behavioral context and parameter understanding.

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 only 33% (1 of 3 parameters described in schema). The description compensates by explaining the directory parameter's purpose ('specific directory to list folders from') and default behavior ('defaults to root'), and mentions recursive behavior in the schema. However, it doesn't address the 'ctx' parameter at all, which remains undocumented.

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 purpose with specific verb ('List') and resource ('folders in the vault or a specific directory'). It distinguishes from siblings by explicitly mentioning when NOT to use it for listing notes or searching content, which are handled by other tools like list_notes and search_notes.

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 explicit 'When to use' scenarios (exploring structure, verifying names, checking existence, understanding hierarchy) and 'When NOT to use' cases with named alternatives (list_notes for notes, search_notes for content). This gives clear guidance on tool selection versus siblings.

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