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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower, and the description still adds real value: it flags that fetched web bodies come wrapped in <untrusted-source> delimiters with instructions to treat them as data, and it identifies the `source` field as the citation URL. Error behavior and size limits are undisclosed, keeping it short of a 5.

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?

Purpose is front-loaded, followed by routing guidance, an example, and a security caveat, in that order. Four tight sentences with no repetition or filler.

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?

No output schema exists, and the description compensates by describing the return shape (frontmatter, body, oa block, source citation field, untrusted-source wrapping). For a one-parameter read tool, nothing an agent needs to call it correctly is missing.

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?

With 100% schema coverage and a single param, baseline is 3; the description adds a concrete example invocation ({"note_id":"eu-ai-act-enforcement-2026"}) that demonstrates the expected id format and its provenance from a search_notes hit. It goes slightly beyond the schema without re-documenting constraints like min/max length.

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 specific verb+resource ('Read one vault note in full') and enumerates what a read returns (frontmatter, body, the oa block). It distinguishes itself from the sibling read_many by scope (single id vs several), so an agent can pick correctly without opening either schema.

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?

Explicitly says when to use it ('a single id from a search_notes hit') and names the alternative with its tradeoff ('for several, read_many is one call instead of N'). This is exactly the when/alternative guidance the dimension asks for.

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