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

Annotations already declare a non-destructive, idempotent mutation, and the description goes beyond them by explaining the note's lifecycle: it influences texts between dates, is consumed in the next date, and is removed by sending an empty note. The consumable/reversible behavior is the key added context, though it does not address permissions or error cases.

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 and effect, then the length/removal rule, with the parenthetical example adding clarity. The phrase 'then it's used' is slightly vague and redundant, but overall the text is tight and purposeful.

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 mutation tool whose annotations cover the safety profile and which has no output schema, the description covers the essential lifecycle and constraints. The remaining gap is undeclared parameter meanings for character_id and 'with' given the low schema coverage.

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 25% (only agent_id is documented), so the description must compensate. It sheds light on the note (length, empty-removal semantics) and implies character_id ('YOUR characters') and 'with' ('someone it has dated'), but the mappings remain implicit and the ambiguous 'with' parameter is never directly defined.

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: leaving a private note on one of YOUR characters about someone it has dated, with a concrete example ('bring up the boat'). It is clearly differentiated from data tools like my_character_memory or forget_memory by describing an effect on future texts and dates, though it does not name any sibling explicitly.

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?

Usage is implied through the effect it describes (colours texts between dates, feeds into the next date), and the empty-note removal rule signals when to clear it. However, there is no explicit when-to-use/when-not or named alternative, so the agent must infer the trigger conditions.

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