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

Annotations only declare the safety profile (readOnly=false, destructive=false, idempotent=false); the description adds real behavioral detail: an archived note is pulled out of Archive onto the top of the list, rescue_count is incremented, last_rescued_at is set to now, and Deleted Notes produce an error. That goes well beyond what the annotations convey and is consistent with idempotentHint=false.

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?

Four short sentences, front-loaded with the primary effect before side effects and the error case. The 'stops sinking' phrasing is slightly informal but still conveys intent compactly; no sentence is redundant.

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 mutation with an output schema, the description covers effect, side effects, the archive transition, and the failure mode. Nothing an agent needs to invoke it correctly is missing.

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?

Only one parameter and schema description coverage is 100%, with the schema already explaining note_id as a UUID obtainable from search, list_notes or fetch. The description adds no further meaning about that parameter, so the 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?

States a specific verb and resource ('move a note back to the top of the list') plus the outcome ('so it stops sinking'), and explicitly contrasts with restore_note for the Deleted Notes case. An agent can distinguish it from siblings without opening any 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 the triggering condition ('when the user wants it kept in view') and names the explicit alternative ('For a note in Deleted Notes, use restore_note'), including that rescue_note errors in that case. Both when-to-use and when-not-to-use are covered.

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