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

Annotations already declare the full safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=false), so the description need not restate it. It adds that the call returns the saved note and that tags/notebook are optional, but says nothing about permissions, duplicate-content behavior, or whether the note is immediately searchable.

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 tight sentences, front-loaded with the use case and alternative routing. 'Returns the saved note' is mildly redundant given an output schema exists, but it costs little and does not bloat the definition.

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 four-parameter, one-required creation tool with an output schema, the description covers purpose, trigger, and the key alternative. The remaining gap is behavioral detail around tags/notebook semantics rather than anything that would block a correct invocation.

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 50%: title and content are documented, but tags and notebook have no schema descriptions. The description only flags that tags and notebook are 'optional', without explaining tag format, whether tags are created on the fly, or whether notebook must already exist. Baseline 3 for a half-documented schema is appropriate.

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 ('save something as a note'), enumerates concrete content types (idea, snippet, meeting jottings), and explicitly distinguishes itself from the sibling create_document for long structured pieces. An agent can route 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?

Gives an explicit trigger ('when the user wants to save something as a note') and names one alternative (create_document) with the condition that selects it. It does not address other note-adjacent siblings such as meeting_notes or search_notes, so the routing picture is clear but not exhaustive.

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