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

Annotations already flag destructiveHint=true and openWorldHint=true, and the description adds real context beyond them: sources are preserved on update, taken slugs are refused, archived notes leave search, the change is immediately visible to every member's agent, and there is no undo. The 'write only what the user stated or confirmed' line plus the cost note ('Free') are exactly the operational details an agent needs before a destructive write.

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?

Front-loaded with the core action, then the upsert rules, then the safety constraints — a sensible ordering with no filler. Sentences are dense and pack multiple clauses (the slug rule alone carries three conditions), which costs a little readability but not substance.

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 six-parameter, no-output-schema mutation with no undo, the description covers mode selection, collision handling, status effects, blast radius (all members' agents) and cost. The only real omission is what the call returns (e.g. the resolved slug), which is minor given no output schema is declared.

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 only 17% (just `body` is documented), so the description must carry the load. It does explain `slug` (update key / collision refusal), `title` (required when no slug, source of derived slug) and `status: archived`. But `tags` and `folder` get no semantics at all, leaving half the surface undocumented.

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 first sentence states a specific verb pair (create/change) and an unambiguous resource (one note in this workspace's second brain), which distinguishes it from the read/search/index siblings. An agent knows immediately this is the write path, not a lookup path.

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?

It spells out the two operating modes precisely: existing slug means partial update with sources preserved, no slug means title is required, slug is derived, and collisions are refused rather than replaced. It also gives the `status: archived` condition for removing a note from search. It does not name sibling tools (e.g. search for an existing slug first), so it falls short of a 5.

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