Summarize Obsidian vault

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

The annotations already declare readOnlyHint=true and openWorldHint=false, so the read-only safety profile is covered. The description adds useful behavioral context by defining the response as a 'compact health snapshot' and enumerating what it returns, plus scoping it to 'the configured vault.' No contradictions or hidden side effects are indicated.

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?

Two tight sentences: the first states the operation and output fields, the second gives usage guidance and an exclusions. Every sentence earns its place with no redundant wording or restating of the title.

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 zero-parameter, read-only statistics tool with no output schema, the description is complete. It explains what the tool returns, when to use it, and what not to use it for, making the tool fully callable without inspecting sibling tools or schemas.

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?

There are zero parameters and schema description coverage is 100%, so the schema carries no burden. The baseline for zero-param tools is 4, and the description appropriately does not invent parameter-related detail. It could have explained the meaning of 'top tags' limits, but that is not required given the simple scope.

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 opens with a specific verb and resource: 'Return a compact health snapshot of the configured vault.' It lists concrete output fields (note count, wikilink count, distinct tag count, top tags) and explicitly distinguishes itself from content-retrieval tools, which is enough to differentiate it from siblings like obsidian_read_note or obsidian_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 gives explicit usage context: 'Use it to understand vault size before browsing' and a clear exclusion: 'do not use it for note content retrieval.' However, it does not name the sibling alternatives that should be used for content retrieval, so the guidance stops short of the most explicit 5-level standard.

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