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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description still adds useful context beyond the annotations: the response is Markdown, it is complete rather than summarized, and it is verbatim ('exactly as published'). It omits error behavior for an unknown slug, which keeps it at 4 rather than 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?

A single sentence, front-loaded with the verb and resource, that spends its words on the format and the completeness of the returned content. Nothing is redundant with the title or the schema.

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?

There is no output schema, so the description must carry the return-value burden and does: it enumerates the fields and content sections returned. The only gap is what happens when the slug does not resolve, which an agent would want to know for a single-item fetch.

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 coverage is 100% and the single slug parameter is fully documented in-schema, including the URL pattern. The description adds nothing about the slug beyond what the schema states, so 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?

Specific verb ('Return') plus specific resource ('one field note') plus the delivery format ('as Markdown') and the exact content envelope (title, date, topic, every section and FAQ). It is clearly distinguishable from the list/search siblings by the 'one ... in full' framing, though it never names them.

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 only implied: the required slug and 'in full ... exactly as published' signal a single-item full read, contrasting with the list/search siblings. It never states when to prefer this over search_notes or related_notes, and gives no exclusions or prerequisites.

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