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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds useful context by specifying what the read returns (title, HTML content, plain text, metadata), which goes slightly beyond the annotations. However, since an output schema exists, much of this return format is already structured, so the description's incremental behavioral value is modest but non-contradictory.

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 with zero filler. The verb and resource are front-loaded, and the return payload is stated in one compact list. Every sentence earns its place.

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 single-parameter, read-only tool with a fully documented schema and an existing output schema, the description is nearly complete. The mention of return fields is helpful even though the output schema covers it, and nothing required to invoke the tool correctly is missing. Slightly redundant given the output schema, hence not a 5.

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%, and the note_id parameter is already described as 'The note ID to read'. The description's 'by its ID' reinforces but does not extend the schema. The description adds no formatting, constraints, or usage nuance beyond what the schema documents, so it stays at the baseline.

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 states a specific verb ('Read'), a clear resource ('note'), and the access method ('by its ID'). This cleanly separates it from siblings like list_notes and search_notes, which list and search rather than fetch a single note. The added return payload details (title, HTML content, plain text, metadata) further pin down what the tool does.

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 implies the use case — fetch a single note's full content when you have an ID — but never names alternatives or when-not conditions. With siblings like get_note-like list_notes and search_notes available, the description leaves choosing between them to inference rather than making the selection explicit.

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