Save a durable note

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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false and openWorldHint=false, so the write/safety profile is covered. The description adds where the note lands (capture folder) and that frontmatter is generated, but says nothing about duplicate-title handling or whether an existing file of the same name is overwritten or rejected.

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 short sentences with zero filler: what it writes, the destination, when to use it, when not to. Purpose and destination are front-loaded before the exclusion.

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 could have stated what the caller gets back (created path/link or confirmation), and it says nothing about duplicate handling for a non-idempotent writer. Everything else an agent needs to select and call the tool is present.

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 80%, so the schema already documents title, body, topics and project. The description's use-case list ('plans, decisions, ideas... logs') loosely maps onto the kind enum, but it adds no syntax, format, or constraint detail beyond what the schema provides. Baseline 3 fits.

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 (write/create) and resource (a new note) plus the destination (the vault's capture folder) and the extra behavior (graph-ready frontmatter). It explicitly differentiates itself from the sibling brain_remember for the one-line-fact case.

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 concrete when-to-use triggers ('plans, decisions, ideas, meeting notes, or session logs the owner wants to keep') and an explicit exclusion with the alternative named ('Not for one-line facts (use brain_remember)'). An agent can route between the two without opening either schema.

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