get_vault_stats

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

Despite no annotations, the description discloses a key requirement (OBSIDIAN_VAULT_PATH must be set) and the read-only nature of the operation is clear from 'Get'. It does not state performance implications or confirm lack of mutation, but for a stats tool no side effects are apparent. It adds the environment prerequisite which is valuable context.

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?

Single sentence, front-loaded with the core purpose, and lists outputs compactly. Every word contributes.

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 simple tool with no output schema, it lists the five statistics returned and the required environment variable. However, it does not specify the output shape (e.g., counts vs arrays), which could be ambiguous for an agent. Still, enough for a basic 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?

The input schema documents the single optional vaultId parameter with a description (100% coverage), so the baseline is 3. The tool description provides no additional parameter semantics beyond the schema, so it neither helps nor hurts.

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 provides overview statistics (total notes, links, orphans, tags, clusters) about a vault. This distinct, specific purpose differentiates it from sibling tools like find_orphan_notes or detect_note_clusters, which focus on individual detailed operations.

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 a use case for high-level vault metrics but does not explicitly contrast with alternatives or mention when to use them. It does provide a clear prerequisite (OBSIDIAN_VAULT_PATH) that helps an agent decide if the tool is usable. However, it lacks explicit 'use this instead of X' guidance.

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