Search the vault

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

Annotations only declare readOnlyHint=true, so the description carries the real burden and delivers: it discloses the return shape (ranked notes with vault path, type/status/created provenance, matching snippet), a conditional behavioral trait (prior-engagement note for previously engaged results), the required plain-language reporting, and the conjunctive matching constraint ('all query terms must match'). That is well beyond the safety hint.

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?

Three sentences, front-loaded with purpose before return shape and the reporting convention. Slightly dense phrasing ('a quiet prior-engagement note', 'as for librarian-recent') makes the middle sentence harder to parse than needed, but nothing is wasted.

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?

With no output schema, the description correctly explains what comes back and even flags the prior-engagement annotation on results. Limit default and ordering specifics beyond 'ranked by relevance' are left to the schema, which is acceptable, but a search tool of this complexity could say slightly more about result ordering or empty-result behavior.

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 100%, so the five parameters are already documented, and the filters (type/domain/status) get no added meaning here. The only reinforcing detail — 'all query terms must match' — duplicates the schema text for `query` rather than extending it. Baseline 3 applies.

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?

States a precise verb and resource — 'Search the user's knowledge vault for notes matching a query' — and immediately characterizes the output (relevance-ranked notes). This clearly separates it from siblings like librarian-get-note (fetch by identity) and librarian-recent (temporal listing).

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?

Usage is implied rather than stated: the agent can infer this is the entry point for query-based retrieval, and it references librarian-recent as a reporting convention. But there is no explicit when-to-use rule, no exclusions, and no guidance on when to prefer librarian-get-note or librarian-positions.

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