obsidian_index

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

With no annotations, the description carries the full behavioral burden. It does disclose that it scans the whole vault, builds/refreshes the index, and that force rebuilds even if the index exists. However, it does not mention cost/latency of a full vault scan, whether an existing index is replaced or preserved, or side effects beyond indexing.

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 compact and front-loaded with the main purpose. The Args section is clearly separated and every sentence/line contributes meaningful information without redundancy.

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 one-parameter tool, the description covers the core action and parameter. Since an output schema is present, not describing return values is acceptable. However, it is not complete enough because it omits when to choose this over index_status and does not warn about the potentially expensive vault-wide scan. It is viable but has clear gaps.

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 provides only a boolean default false with no parameter description, so the description must compensate. It does so fully: the 'force' argument is explained as 'rebuild the index even if one already exists,' which adds real semantics beyond the schema.

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, actionable verb and object: 'Scan the vault and build/refresh the embedding index.' This clearly identifies what the tool does and distinguishes it from siblings like obsidian_index_status (checking status vs building) and obsidian_search/obsidian_rag (querying vs indexing).

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?

There is no guidance on when to invoke this tool versus alternatives. It does not mention checking obsidian_index_status first, nor does it say when a refresh is needed or when a rebuild with force is appropriate. The only implied context is that the tool is for building an index, but no exclusions or alternative routing are provided.

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